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fast_97_240sx
05-14-2006, 04:36 PM
I've seen alot of people asking what different turbos and setups will make them. Here's what I made and my setup. Hope this helps.

1990 240sx
1994 SR20DET Blacktop (Painted red)
Top Speed intake manifold
DC Sports turbo manifold
Garrett GT28RS .64
Precision 880cc injectors (I'll do a bigger turbo later)
Koyo radiator
Blitz FMIC
Eagle H-Beam rods
CP pistons
Greddy rocker stoppers
Greddy head gasket 1.2mm
JIC catback SS something
3" downpipe "Ride Revolution" custom
Ride Revolution chipped and tuned ECU


http://i72.photobucket.com/albums/i161/darkwhip/DSCF0646.jpg

The timing is set conservatively. The A/F ratio was 12.5 across the board. I had about a gallon of c16 mixed with 5 gallons of 93. Boost was set to approximately 21psi.

_Def_
05-14-2006, 04:38 PM
That on stock cams? Lots of torque.

240_kid
05-14-2006, 04:43 PM
Werd dude
Thats alot of Trq.
Talk about Trq. Monster http://forums.freshalloy.com/images/graemlins/tongue.gif

fast_97_240sx
05-14-2006, 04:43 PM
Yes
I have a set of Tomei 270s waiting on the rest of the valve train. When I can afford the rest we will retune and I'll repost. maybe awhile - I'm broke LOL

OH yeah the SAE corrected numbers are
343.4 power
380.5 torque

I know someone on here will cry about that.

yellowmunson
05-14-2006, 05:15 PM
The timing is very conservatively, and just boosted up little. from GT28RS compressor map, it should be close to maxed out on it. However, it will make more power with right combination of cams and valve timing on same boost. whenever he tells me to work on it http://forums.freshalloy.com/images/graemlins/rolleyes1.gif.

its a burn out king for sure.

fast_97_240sx
05-14-2006, 06:06 PM
Thanks again Mr.Munson

Your the shizzle.
I promiss I'm not abusing it http://forums.freshalloy.com/images/graemlins/Angel_anim.gif

IKnowNothings
05-15-2006, 02:36 AM
wow, just wow
thats more power than many people are making with the GT2871R
get the cams in and re-dyno soon!!
Are you happy with it or do you want more?

fast_97_240sx
05-15-2006, 07:26 AM
I'm very happy. I drive the car on aprox 10psi and I have a dual stage boost controller so I can switch to 15psi (makes about 290whp)when needed lol. I wanted Scott (yellowmunson) to push the numbers up a little so he could show people his ability. Keep in mind this is still conservative. He said he could probably make it pull 400hp but the torque has pretty much leveled out and I have a crappy clutch. He tuned it for me to beat the crap out of it. The car was tuned on the street, it went to the dyno just for the printouts. My A/F is perfect my power is more than I need so yes I'm stoked. Alot of people on here use mailorder tunes which are great but never seem to be right (in my opinion and previous experiences). Nothing like having the tuner actually drive the car.

scotheocelot
05-15-2006, 08:30 AM
I agree with that statement but how is he tuning your ROM on the fly? Dont you have to take it out, burn it then put it back in the ECU? If thats the case, how come Scott cant save this tune (if its conservative) and offer it to people who mail in their ECU? Sounds to me like what Enthaply does. If you cant get to Florida or fly him to where you are, thats the best but some people just dont have the means. Where is your tuner located?


-scott

ps: those are incredible numbers for that setup!

fast_97_240sx
05-15-2006, 08:59 AM
Sorry if I made it sound like it was on the fly.Tuning on the dyno(Dynojet in this case) doesn't produce the same load as being on the street. He has to take the chips out. He starts by putting in the tune that IS saved, then takes it out on the road comes back and makes mods. If you mail it to him he can put a tune in but ALL cars and most enviroments are different so even with the same setup as me someone else's car may not react the same. Then it's up to the owner to give Scott feedback and/or dyno results to complete the tune from there. He is located in Johnson City TN www.RIDEREVOLUTION.com (http://www.RIDEREVOLUTION.com) . My problem with the mail order tunes is that most people(that I've been around) put the tune in and that's the end of it, I dont see that as tuning thats a bandaid when you need stitches.

gatecrasher
05-15-2006, 11:53 AM
those are impressive numbers......but i think 400rwhp with that turbo is pretty wishful thinking if you're already at 12.5:1, on a leaded gas mix, and 21psi.

great numbers though. should be fun to drive

yellowmunson
05-15-2006, 12:25 PM
well anything is possible..
considering GT28 compressor map is maxed out but oh well.

with cams and valve timing. I am pretty sure I can make it there with 40psi http://forums.freshalloy.com/images/graemlins/tongue.gif

gatecrasher
05-15-2006, 03:00 PM
well anything is possible..

with 40psi http://forums.freshalloy.com/images/graemlins/tongue.gif





http://forums.freshalloy.com/images/graemlins/grin.gif

fast_97_240sx
07-20-2006, 09:03 AM
those are impressive numbers......but i think 400rwhp with that turbo is pretty wishful thinking if you're already at 12.5:1, on a leaded gas mix, and 21psi.

great numbers though. should be fun to drive



Well we got 403 lastnite only changes were we added my HKS 270 cams w/Tomei cam gears. I'll get the graph up today or tomorrow.

forcefedS13
07-20-2006, 09:36 AM
I believe that is the GT28RS record. Am i wrong?

Impressive numbers, congratulations.

champa
07-20-2006, 02:53 PM
Impressive but how practical is 12.5:1 afr on the street or on a road course?

IKnowNothings
07-20-2006, 03:12 PM
Holly hell batman
That’s insane making that kind of power with the potato.
This thread is making it more difficult for me to choose a turbo now.
potato or gt2871r lol

forcefedS13
07-20-2006, 04:19 PM
2871R is more consistent.

TS4l
07-20-2006, 04:24 PM
Impressive but how practical is 12.5:1 afr on the street or on a road course?

It really depends on the tune, my last car ran 12.5:1 and lasted two years until I sold it, and as far as I know its still running. However I would think with the way this thing must be pushed to make these numbers it does seen scary to me. Very impressive numbers I hope it runs great for you for years.

chunk
07-20-2006, 09:37 PM
This thread is making it more difficult for me to choose a turbo now. potato or gt2871r lol

I totally disagree... Look how badly his TQ falls off. I'm not hating on this guys setup, but hell would freeze over before I chose a DP over a GT2871R .86

In_DET
07-20-2006, 10:35 PM
So whats it do on pump gas?

Racingswh
07-20-2006, 10:47 PM
I totally disagree... Look how badly his TQ falls off. I'm not hating on this guys setup, but hell would freeze over before I chose a DP over a GT2871R .86

For what application? Street car?

I am using the 2871 .86 now and based on that dyno chart I am considering this turbo or at least changing the housing to the .64. Lot's of off corner lag with the .86 especially in the wet where you can't go flat out through corners.

I want to see the dyno with cams. Even better would be to see a dyno with it tuned at 11.3 - 11.7 afr and 18 psi.

fast_97_240sx
07-21-2006, 12:29 AM
I think hell did freeze over, anyway. Haven't done the street tune on it yet,we'll prob go around 330 for daily driving. The car is a blast I have the RS now just for numbers I'm planning on switching to a GT35R. It seems like 400whp is the golden number for 2871R and only a few seem to get it (my opinion from what I've read here.) So Scott and I wanted to see what it would take to get to that number on the RS. Is the car reliable? I don't know and I don't have the money to find out so we'll turn it back down in a few days. Scott beat the crap out of the car on the street, on the dyno and tonight at the track with the help of Tanaka Hiromi "Garage Paddy" ( http://www.paddy.co.jp/ ). They got the car to run 12.27 @ 117.49 @ Bristol Dragway in Bristol TN. I know alot off you have run faster on less power but come to Bristol and you'll understand this is fast. Sorry for the crappy pics of the graphs. We were letting out around 5500rpms due to my POS eBay clutch (XTD I'm broke it's all I could afford) slipping you can see from 4200 how bad we were blowing through it. OH Yeah, I dont debate about the times the car or the tuning If you think your better or know more or whatever GREAT keep negative comments to yourself it just makes you sound like a l)1ck.



http://i72.photobucket.com/albums/i161/darkwhip/DSCF0773.jpg

fast_97_240sx
07-21-2006, 12:33 AM
Holly hell batman
That’s insane making that kind of power with the potato.
This thread is making it more difficult for me to choose a turbo now.
potato or gt2871r lol
Please don't use my example to sway your decision. If you want good power 350 - 400 go GT2871R it is the better way to go. And buy a good clutch.

chunk
07-21-2006, 12:49 AM
^^well said^^

yellowmunson
07-21-2006, 12:57 AM
that was on 22lb on boost, but it has 10lb springs on actuator with crappy turbo xs manual boost controller. boost goes to 22lb and back to 14lb shortly after the peak boost. I am pretty sure it will make more stady power and tq curve with cotrolling boost in better way. but I did this just for fun..

it did put 416rwp with bad slipping clucth on 4th gear and I had to pull on 3rd instead. and it didnt record it because I stopped it shortly after the hard slip on clucth.

it was pretty fun and paddy did get to drive in U.S 1/4 miles track so ..its all good.

and also valve timing/ and I could of put more overlap, but I didnt want it to stall out on street car.

this was done on my old race gas mix with 93octane

I will pull up 18.5 lb dyno sheet tomorrow. I have plx wideband on this car insde and dyno wideband is just used at the end of tail pipe. which makes just little leaner. on my wideband it is 11.8 all the way across.



Please don't use my example to sway your decision. If you want good power 350 - 400 go GT2871R it is the better way to go. And buy a good clutch.

_Def_
07-21-2006, 09:03 AM
Somthing is wrong with that dyno - it would take a retarded amount of boost to make an SR20 put out almost 390 rwtq. If you say the boost drops down to 14 psi after the initial spike, then how is it making 340 rwtq at the LOWEST point? 14 psi on one of these engines gives somewhere around 250-280 rwtq.


Keep in mind it's very hard to significantly increase the max torque of an engine at a given boost once it has basic breathing mods on it, but it can be changed where that peak torque occurs(changing HP and powerband). You pretty much get close to perfect cylinder filling at least one place in the RPM range with a mostly stock engine, so I just can't see how you're making probably 40-60 ft-lbs more torque than you really should be at the boost level you're running.


Yes, I know - more timing from better gas helps, but I don't see it being that big of a difference.

2slow240sx
07-21-2006, 09:50 AM
Somthing is wrong with that dyno - it would take a retarded amount of boost to make an SR20 put out almost 390 rwtq. If you say the boost drops down to 14 psi after the initial spike, then how is it making 340 rwtq at the LOWEST point? 14 psi on one of these engines gives somewhere around 250-280 rwtq.


Keep in mind it's very hard to significantly increase the max torque of an engine at a given boost once it has basic breathing mods on it, but it can be changed where that peak torque occurs(changing HP and powerband). You pretty much get close to perfect cylinder filling at least one place in the RPM range with a mostly stock engine, so I just can't see how you're making probably 40-60 ft-lbs more torque than you really should be at the boost level you're running.


Yes, I know - more timing from better gas helps, but I don't see it being that big of a difference.

I agree with you, Def. It just doesn't add up. How can cams and timing make a turbo compressor flow more lb/min than it's physically capable of flowing?

I live in Knoxville, so I would be interested in doing some dyno comparisons. I would like to do some runs @ RR and overlay them with the runs made here in Knoxville.

Please, don't take this as a bash or negative comment to bring anyone down. Not meant that way at all. I'm sure the car is haulin' arse, regardless of pretty numbers on a shiney printout. 12's @ Bristol is not too shabby.

On a side note...RR has the highest hp record on stock bottom KA? I'm interested in knowing more about this, but that's a different thread.

BillKlineVT
07-21-2006, 11:18 AM
Awesome job tuning Scott, man I wish I could've gotten down there to see what Paddy and you could do with my timing map. (This is Bill btw, friends with Rhombus and Jeff).

Def, I doubt there's any trickery going on here, Scott and the guys at RR are definitely reputable. It's inevitable that people will get su****ious when records are broken, such as when Jeff broke the stock bottom end KA record (528 whp / 420 wtq) - coincidentally at this same dyno.

champa
07-21-2006, 11:30 AM
some dynos are more optimistic than others from what i've seen. take it to another dyno and see if it puts down the same numbers.

_Def_
07-21-2006, 05:43 PM
Awesome job tuning Scott, man I wish I could've gotten down there to see what Paddy and you could do with my timing map. (This is Bill btw, friends with Rhombus and Jeff).

Def, I doubt there's any trickery going on here, Scott and the guys at RR are definitely reputable. It's inevitable that people will get su****ious when records are broken, such as when Jeff broke the stock bottom end KA record (528 whp / 420 wtq) - coincidentally at this same dyno.

I'm not saying anybody doesn't know what's going on, I'm just a firm believer in thermodynamics and fluid dynamics - you just aren't going to get that much OOMPH out of that much cylinder pressure on an SR(torque) - nor are you going to make a compressor pump out 30% more weightflow than it can do at the ass end of its lowest efficiency island.

The car is fast I'm sure, I'm just doubting it's making near 400 rwtq.

Racingswh
07-21-2006, 06:58 PM
The car is fast I'm sure, I'm just doubting it's making near 400 rwtq.

Hi Def

I am glad you chimed in on this. Looks like it was making 387 on the stock cams. What do you believe it's really making or can make? All of your predictions have been spot on at the dyno's I am using. You told me that my SR would have a hard time making over 330 with stock cams and my 2871 .86 and I am at 329 and change and 305 rwtq.

I was wrong about what would make a good roadrace turbo. I was even considering spraying (nitrous) my current set up at low boost levels until I found out it's illegal in my race series. I think this turbo (DP) maybe the best available at this time for our SR engines. Not open track or lapping days where the 2871 gets to stretch it's legs a bit and let everyone have it but racing where all the damn traffic dictates lap times. You need something that makes good tq lower in the rpm range so you're not having to goof around with the gearshift lever everytime you need to get by someone at trackout and then have to shift immediately which wastes even more time. You know what I mean. What do you think? I think this setup may be the best all around for many applications. This thread comes at a perfect time as I am trying to decide on my setup for next season.

Even if it's an optimistic dyno this thing puts down over 100% more tq at 4000 rpm than my current setup. I am inclined to believe that because my T28 made 265 at 3600 rpm and my junk now makes about 120 rwtq at that same level. I don't think the dyno tune of this particular engine would allow me to subject it to the torture for very long but scaled back a bit it should work pretty damn well.

I happen to like this guy's setup for me even if the charts are optimistic. My guess is in a 50 mph 3rd gear roll on with big sticky slicks this thing flat out flies! 1/4 mile times were pretty good as well and with clutch and tires my guess is it has more to give.

Some will say the .64 housing but I am leaning towards this thing. Looks like there is a 3 day old 2871 .86 for sale. lol!

Oh and Fast 97 if you're really selling this RS PM me. I would be interested.

_Def_
07-21-2006, 08:50 PM
Looking at the compressor map it seems even more dubious, at full spool he's almost off the compressor map, then proceeds to make another 30-40 rwhp over that. I was being very generous on where I was putting the spot, I'd probably say 320rwhp on these engines is a hair more than 35 lb/min. I assumed no pressure drop through the intercooler/piping as well. He's probably more like a 2.5-2.6 PR, which is even harder to achieve as you can see the compressor's speed lines are falling like a rock there(i.e. compressor is going to have to exponentially accelerate there to get the tiniest bit of flow).

-edit- forgot to include the compressor map point - here it is at spool up, much less power than it is making later on -edit-

http://img107.imageshack.us/img107/8610/gt28rsmapwtfyl1.jpg

The reason why these engines don't make over ~330rwhp on stock cams is that the intake ports go sonic for most the intake event, so it doesn't really matter how much pressure you put across them - they'll always flow about the same amount(probably around 35-37 lb/min). Add cams and you now have lots of port flow and can actually flow more with a higher pressure differential(i.e. more boost).

The fact that with stock cams he's making 350rwhp with a turbo that really shouldn't be able to do that regardless of the engine it's on is just even more suspect.

dryft_s15
07-21-2006, 08:56 PM
The reason why these engines don't make over ~330rwhp on stock cams is that the intake ports go sonic for most the intake event, so it doesn't really matter how much pressure you put across them - they'll always flow about the same amount(probably around 35-37 lb/min). Add cams and you now have lots of port flow and can actually flow more with a higher pressure differential(i.e. more boost).

The fact that with stock cams he's making 350rwhp with a turbo that really shouldn't be able to do that regardless of the engine it's on is just even more suspect.

Not that I'm taking sides, especially since I've hit that ~330whp limit myself, but isn't this only applicable to pump gas?

With race gas (or a mix), coupled with the associated tuning adjustments, I'm sure over 330whp is possible.

Racingswh
07-21-2006, 09:18 PM
Not that I'm taking sides, especially since I've hit that ~330whp limit myself, but isn't this only applicable to pump gas?

With race gas (or a mix), coupled with the associated tuning adjustments, I'm sure over 330whp is possible.

Mine is not able to. I run 108 synthetic race gas in mine. Actually set up fairly safe how I race it, 18 degrees of timing and 11.3 afr above 4k and 18 psi, it makes a little less.

My engine has been pounded on over 1 1/2 years of race track use and it's on the tired side so it isn't the best example. Others may make more.

2slow240sx
07-21-2006, 09:28 PM
Race gas can't make a turbo flow more than it's designed to flow. A turbo designed to flow around 36lb/min can't make over 400whp as a single turbo setup.

Wa = HP * AFR * BSFC / 60

This formula, using AFR of 11.8 (stated by munson on the PLX) and BSFC of .55, means 400 hp needs 43.26 lb/min of air. That's for bhp, not whp. A properly sized turbo seeing IAT's around 130*F, @ 92% VE would need to see somewhere around 26psi to make 400bhp on this 2.0L engine. Maybe the VE is closer to 99% with the cams, but I seriously doubt that he made this on "19psi, falling to 14psi" on a turbo that can't flow more than 36lb/min.

dryft_s15
07-21-2006, 09:32 PM
My consideration is more for the 350whp part, specifically going past the 330whp barrier we all seem to hit with the stock valvetrain.

I can't see the turbo making 400whp either.

Racingswh
07-21-2006, 09:43 PM
Race gas can't make a turbo flow more than it's designed to flow.

I interpreted that as being able to run more aggressive timing and boost levels because of the race gas in the quest for more power.

I tried and with my 2871 .86 and stock cams 330 was the ceiling for my set up.

forcefedS13
07-21-2006, 11:42 PM
330whp maximum seems low for a .86AR 2871

Im personally chasing the .64AR record and looking for 385-400whp. Most say it cant be done. I want to prove them wrong.

I think the tune had alot to do with this power rating. Most disagree that the SR wil put out that kind of power when youve gone beyond the turbos max flow rate, but it seems to have been done more than once, and more than just one car.

yellowmunson
07-22-2006, 12:40 AM
22lb to 14lb I wrote.... but anyway.. I dont have time to ague here so let it be alone.

18.5lb was a pull on street tune.. which was 11.8 AF. it was about 372 ish not a 400rwp.

I was going to pull some 18.5lb dyno sheet but I dont have time for hater or whatever. so let it be. all dyno pulls was legit.
race gas or pump gas has nothing to do with compressor map on turbo, its only purpose of decresing chance of getting more knock and detonation.
my datalogger shows at duty cycle and caculated to about 415 without any kind of clucth slippage


Race gas can't make a turbo flow more than it's designed to flow. A turbo designed to flow around 36lb/min can't make over 400whp as a single turbo setup.

Wa = HP * AFR * BSFC / 60

This formula, using AFR of 11.8 (stated by munson on the PLX) and BSFC of .55, means 400 hp needs 43.26 lb/min of air. That's for bhp, not whp. A properly sized turbo seeing IAT's around 130*F, @ 92% VE would need to see somewhere around 26psi to make 400bhp on this 2.0L engine. Maybe the VE is closer to 99% with the cams, but I seriously doubt that he made this on "19psi, falling to 14psi" on a turbo that can't flow more than 36lb/min.

2slow240sx
07-22-2006, 06:17 AM
330whp maximum seems low for a .86AR 2871

Im personally chasing the .64AR record and looking for 385-400whp. Most say it cant be done. I want to prove them wrong.

I think the tune had alot to do with this power rating. Most disagree that the SR wil put out that kind of power when youve gone beyond the turbos max flow rate, but it seems to have been done more than once, and more than just one car.

Exhaust A/R has nothing to do with the amount of flow possible on the cylinder head, which is where the 330whp max comes into play. The head, with stock cam profile, can't flow enough lb/min to make more power. It's not an issue of the exhaust housing choking out the flow.

2slow240sx
07-22-2006, 06:18 AM
my datalogger shows at duty cycle and caculated to about 415 without any kind of clucth slippage

I don't even know what you just said, but it doesn't matter.

forcefedS13
07-22-2006, 10:03 AM
Exhaust A/R has nothing to do with the amount of flow possible on the cylinder head, which is where the 330whp max comes into play. The head, with stock cam profile, can't flow enough lb/min to make more power. It's not an issue of the exhaust housing choking out the flow.

Than where is the arguement? He made 370+ on a DP. Thats unheard of, and everyone said it cant be done because it surpasses the max flow rate.
Maybe i missed something.

fast_97_240sx
07-22-2006, 11:55 AM
Than where is the arguement? He made 370+ on a DP. Thats unheard of, and everyone said it cant be done because it surpasses the max flow rate.
Maybe i missed something.


MY car is fast :hsdance:

If you all don't stop arguing about it I'll buy a 2871 and make Scott tune it to 475 (random number haven't asked him about this yet). :26:

2slow240sx
07-22-2006, 12:43 PM
^^^ I like that attitude. Regardless of the accuracy of any numbers, I'm sure that the car flies at the boost levels you're hitting. I'd say forget the hype of the numbers and hit the strip for some fun.

_Def_
07-22-2006, 01:04 PM
Than where is the arguement? He made 370+ on a DP. Thats unheard of, and everyone said it cant be done because it surpasses the max flow rate.
Maybe i missed something.

The argument is that hes so far off the compressor map to make 400rwhp on a DP it's not even funny, then on top of that, he makes 350rwhp and near 400rwtq on stock cams. Both of those points are *really* hard to get to on the compressor map, and it's already been proven that it's hard to get past about 320-330rwhp on stock cams. A bigger turbine A/R with stock cams is only going to make it easier to choke the intake ports, with a small .64 A/R it seems like most engines struggle a bit to get up to that level(due to excessive exhaust residual).

fast_97_240sx
07-22-2006, 03:17 PM
Hey come to the shop I'll run it for you, street, dyno, dyno @ a competing shop (you pay though).

MY car is so fun :woohoorun:


I think maybe ... nevermind.

KB240SR
07-22-2006, 04:00 PM
he does have a Top Speed Intake Manifold if that matters. I figure that would give more flow even with stock cams to produce some good numbers. I know with my setup on the 2871R i gradually loose torque from the stock intake mani but horsepower keeps rising to almost 7k rpms from the HKS 264 cams. if i still had stock cams, im sure torque would be higher than i have now but the horsepower wouldnt keep rising like it does. Congradulations on the awesome numbers.

KB240SR
07-22-2006, 04:02 PM
fast 97 240sx, have you thought about a larger turbo elbow. it should help keep boost at higher rpm. my stock elbow makes my 2871R drop from 19psi to 15-16psi by redline.

fast_97_240sx
07-22-2006, 04:04 PM
Thanks.

Racingswh
07-22-2006, 04:42 PM
You do have to admit that 2slow240 and Def have facts and formulas to back up their questions about the stated power on the charts. As I mentioned before Def's info for me in the past has been correct. He is good at interpreting data and breaking it down. Obviously 2slow240 is pretty good at it as well. Going even further there are a number of 240 SR and KA guys on this forum that are extremely knowledgeable. It's tough to state something that looks out of the ordinary and not be questioned about it. Without all of the help I have gotten from here and from my builder my car wouldn't be anywhere near as fast and reliable as it is today.

For me I happen to like when and how the DP makes power. It can make 350 rwhp or more with cams at 6000 rpm or so, easily makes over 300 rwtq and begins making power at 3500 rpm so it looks like this is the turbo I want for my purposes.

_Def_
07-22-2006, 04:59 PM
He is good at interpreting data and breaking it down.
I should hope so, it's what I do everyday during the week! :) (I'm a fluids and thermal test engineer)

s14rhd
07-23-2006, 10:40 PM
I would say the dynos off somehow MPH is low and yeah with that turbo on stock cams..... :auto: I

KB240SR
07-23-2006, 11:56 PM
is anyone here taking in the consideration of the Intake Manifold or doesnt that matter? I always thought the stock cams and stock intake manifold limited the SR to around 350whp. You increase either one and the power level should increase.

2slow240sx
07-24-2006, 04:49 AM
is anyone here taking in the consideration of the Intake Manifold or doesnt that matter? I always thought the stock cams and stock intake manifold limited the SR to around 350whp. You increase either one and the power level should increase.

Cams and intake manifolds can't make a turbo compressor flow anymore air than is physically possible.

forcefedS13
07-24-2006, 09:00 AM
Youre right, it cant...but the compressor map doesnt limit the amount of power the engine was already making before the turbo was bolted on and raised to the max.

congrats dude. have fun with it. sounds like one helluva street beast.

tErbobOOst
07-24-2006, 11:42 AM
It seems to me that the Dyno being used is either broken, or EXTREMELY optomistic.

fast_97_240sx, No doubt a car with ~350whp is fast and fun. Good job on the setup and I wouldnt doubt if you are pushing the limits of the compressor.

However, you can push the limits...you can not break them. The fact that his T25 dyno is also EXTREMELY high, and now this dyno is as well, it sounds like you need to take the car onto another dyno.

congrats on the numbers, and you being extremely happy with the car (isnt that what its all about)...but if you have been reading anythign Def or 2slow240 has said you should be reconsidering waving around those numbers before putting it on another dyno...I know I would.

WikedSicc
07-24-2006, 12:17 PM
I am willing to bet the load bearings on the dyno are off.

What is the altitude correction set for on the dyno?

2slow240sx
07-24-2006, 04:22 PM
Youre right, it cant...but the compressor map doesnt limit the amount of power the engine was already making before the turbo was bolted on and raised to the max.

congrats dude. have fun with it. sounds like one helluva street beast.


I think you're trying to say that the engine's NA hp can be combined with the potential hp of the turbo, resulting in a higher hp than the turbo can handle...

If I'm understanding your statement correctly, then I'll tell you that you're incorrect. It doesn't work that way.

forcefedS13
07-25-2006, 10:24 AM
okay.

SRENITY
07-25-2006, 03:43 PM
I agree that the numbers seem way to optimistic for the turbo. The only thing that has not been mentioned is the VE of the engine. The turbo it self is not going to miraculously pump more air than it was designed to. So in order to make more power than others with the same turbo the engine has to be more effiecient as an air pump. This amount of power however I would consider outside of the range even with an extremely high VE. If I had more time and cared more about it I would plug some numbers into the ideal otto cycle formula to see if it is even theoretically possible.

2slow240sx
07-25-2006, 04:07 PM
You can usually associate VE with the torque line on the graph. In one of my calculations I think I used 95% VE as an example. Even if it's as high as 99%, the numbers posted are hardly possible.

b18c_ferio
07-25-2006, 04:56 PM
can it be possible that this is a high compression motor, therefore having a higher "effective" compression ratio(more power)?

2slow240sx
07-25-2006, 05:07 PM
High compression doesn't = more lb/min through the engine. Sure, the offboost response and power would be more, but not necessarily the on-boost operation. Also, the cams would lower the dynamic compression, somewhat, with the overlap and all.

I doubt that he's running more than low 9:1 range, since he's pushing 22psi as a peak boost pressure.

Jeff Taylor
07-25-2006, 09:25 PM
Yikes! I just now came across this thread.

First off: Those are very impressive numbers. Much respect to all involved in the creation of that beast! Now, I'm reluctant to spend the next hour refuting arguments here...but I have plenty of beer in the fridge..so here it goes:


Somthing is wrong with that dyno

Something is wrong with the dyno? Ok. That one I'll just laugh at.


it would take a retarded amount of boost to make an SR20 put out almost 390 rwtq.


Since when is boost absolutely proportional to torque, despite what engine VE and turbo is used?



14 psi on one of these engines gives somewhere around 250-280 rwtq.

Again. 14psi == 250-280rwtq? Is that on a T25 or a GT45? Do you realize that there are flow differences between those turbos? Obviously not.



You pretty much get close to perfect cylinder filling at least one place in the RPM range with a mostly stock engine.

What do you consider "perfect"? 100%? 120%? 300%?

Jeff Taylor
07-25-2006, 09:37 PM
I'm just a firm believer in thermodynamics and fluid dynamics - you just aren't going to get that much OOMPH out of that much cylinder pressure on an SR(torque)



Me too buddy. Define OOMPH. I'll assume your OOMPH is called torque.

Since when is cylinder pressure absolutely proportional to boost pressure on various turbos? Again, T25 @ 20psi vs. GT45 @ 20psi? Which one do you think will produce higher cylinder pressures? Please don't tell me that they would be equal. Afterall, BMEP IS PROPORTIONAL TO TORQUE.

Jeff Taylor
07-25-2006, 09:46 PM
The reason why these engines don't make over ~330rwhp on stock cams is that the intake ports go sonic for most the intake event, so it doesn't really matter how much pressure you put across them - they'll always flow about the same amount(probably around 35-37 lb/min). Add cams and you now have lots of port flow and can actually flow more with a higher pressure differential(i.e. more boost).


That's funny. It makes me wonder why several sr20's I have seen make pulls on the dyno have produced over 330whp on stock cams and intake manifolds. Those dyno's must be wrong too.

And even with an altered intake runner length and cross-sectional area, it still won't flow any more than 35 - 37 lb/min? Wow. That's news to me as well.

Jeff Taylor
07-25-2006, 10:20 PM
Race gas can't make a turbo flow more than it's designed to flow. A turbo designed to flow around 36lb/min can't make over 400whp as a single turbo setup.



How about nitrous? How about fuel with a higher energy content than pump gasoline?

Jeff Taylor
07-25-2006, 10:31 PM
I'm done pissing. Please piss back.

s14rhd
07-25-2006, 10:47 PM
You made a few mundane comments, Def knows which turbo the poster has and is talking about that (GT28RS) obviously. It common knowledge that stock SR's will not not flow much more 330whp on stock cams this board is littered with dyno graphs which prove this.

Do you have any proof to back up your statements showing SR's making more then 330whp with stock cams without very big turbos?

No point in arguing just for the sport, lets see some proof?

fast_97_240sx
07-25-2006, 10:50 PM
You made a few mundane comments, Def knows which turbo the poster has and is talking about that (GT28RS) obviously. It common knowledge that stock SR's will not not flow much more 330whp on stock cams this board is littered with dyno graphs which prove this.

Do you have any proof to back up your statements showing SR's making more then 330whp with stock cams without very big turbos?

No point in arguing just for the sport, lets see some proof?

Umm did you look at the first post of this thread?

Jeff Taylor
07-25-2006, 10:56 PM
You made a few mundane comments, Def knows which turbo the poster has and is talking about that (GT28RS) obviously. It common knowledge that stock SR's will not not flow much more 330whp on stock cams this board is littered with dyno graphs which prove this.

Do you have any proof to back up your statements showing SR's making more then 330whp with stock cams without very big turbos?

No point in arguing just for the sport, lets see some proof?

Sure. Here's one S13 we tuned. 389wHP with stock cams (2nd from bottom):
http://www.rhombus-net.com/rhombus/nissan/dyno.htm

When I come across some others I'll post them.

fast_97_240sx
07-25-2006, 11:13 PM
Maybe if you guys would spend your time trying to make this kind of power instead of trying to figure out why we can't, you wouldn't be strapped by your limits.
If you want to argue about the dyno then you'll need to go to a Chevy or Ford forum and take it up with them cause they say our dyno reads low. Their 500hp V8 making 265. Thats an argument you don't, want they drink BUD.

fast_97_240sx
07-25-2006, 11:19 PM
Boy I can't wait to here all the **** when I get my GT35R and put the big cams in. I have a bad ass nitrous setup laying in my basement.

_Def_
07-25-2006, 11:27 PM
That's funny. It makes me wonder why several sr20's I have seen make pulls on the dyno have produced over 330whp on stock cams and intake manifolds. Those dyno's must be wrong too.

And even with an altered intake runner length and cross-sectional area, it still won't flow any more than 35 - 37 lb/min? Wow. That's news to me as well.

You can make slightly over 330rwhp, I've seen it, I'm saying that's usually the "practical limit." The more delta P you put across the intake valves the more you increase the VE by virtue of a greater intake/exhaust pressure differential. You're still making the valve throat area go sonic and that is what is choking your flow.

It doesn't really matter what you do with port tuning at that point, as a few psi increase in static/total pressure isn't going to matter when the flow is choked.

Go read up on some compressible fluid dynamics, you seem to be missing my point about choked flow.


Don't have time to respond to the other "nitpicking" since I worked 13 hrs today, but it's all pretty inconsequential to the points I made.

Oh yea, it sounds like you're of the "Honda mindset" whereby a bigger compressor wheel magically "flows more air" at the same intake manifold pressure. hahaha

s14rhd
07-25-2006, 11:30 PM
Maybe if you guys would spend your time trying to make this kind of power instead of trying to figure out why we can't, you wouldn't be strapped by your limits.
.Heh I do, that why I am buying cams soon so I can make around 360whp, my stock cams are limiting me and my gt2871r from making anymore then about 330whp the torque just drops off.

I'll have a look at those graphs soon Jeff.

fast_97_240sx
07-25-2006, 11:33 PM
It's not your cams, It's your tunner or tunning or maybe something else in the mix. Bring it to Scott he'll get you straight.

Jeff Taylor
07-25-2006, 11:52 PM
Go read up on some compressible fluid dynamics, you seem to be missing my point about choked flow.


I understand your point on choked flow. However I do have a problem with you stating that there is something inherently wrong with the dyno pulls because they do not agree with your "rule of thumb" on the maximum whp an sr20det can produce with stock cams.

Your rule of thumb is wrong. So perhaps you should reconsider your compressible fluid dynamics analysis of the sr20.

...and yes, there is more to the analysis of engine dynamics than "big turbos flow more air than smaller ones"; my point was merely used for you to reconsider your statement.

I can wait for your other responses since you don't have time tonight. You know as well as I that they are equally relevant.

Before this gets any dirtier (which it will), I want to say that no matter if I'm wrong or you're wrong, at least one of us will come out with a better understanding on the subject.

_Def_
07-26-2006, 12:11 AM
Before this gets any dirtier (which it will), I want to say that no matter if I'm wrong or you're wrong, at least one of us will come out with a better understanding on the subject.

You have some sort of problem here? You seem to have a stick up your ass about my posts judging by your tone and diction.


I really don't have anything to prove here, I know more than enough about the subject material I brought up that I have the upmost confidence in the validity of what I posted.


If you don't see how a 2.0L engine with 18 lb/min max weight flow turbine housing and 21 psi of boost shouldn't be making near 400rwtq, and then blame everybody's skepticism on "not having good tuners," I just don't see where else we can really go from there. I've said my part, I know what I'm talking about, and all I see from your side is nitpicking of my semantics. Come back with something substantial if you want a meaningful conversation about this.

Jeff Taylor
07-26-2006, 12:40 AM
Oh well, we got somewhere: we disproved the "330whp" rule.

KB240SR
07-26-2006, 12:46 AM
My friend made 325whp @ 18psi with a 10.0 AFR using a 2871R .64. He is on stock cams but has a Greddy Intake Manifold. I find it hard to believe that stock cams are restrictive to 330whp because once he gets his car tuned to 11.5 or better AFR, it will no doubt be at 350whp or over on the stock cams. Someone explain please? The power might be restricted with stock cams AND stock intake manifold to 330whp but i think if you upgrade the intake manifold, the added air will help achieve higher numbers even with stock cams.

smithers584
07-26-2006, 01:28 AM
Well my SR makes 550 rwhp on the stock fuel and stock turbo/intake mani/cams, well thats if you add in the power from the Land Cruiser thats pulling the trailer its sitting on!

Just trying to ease the tension.

s14rhd
07-26-2006, 01:54 AM
Oh well, we got somewhere: we disproved the "330whp" rule. Nobody said it was dead set at 330whp it is around there that most people find there limited to. We have perhaps proved your a nit picker without any real relevant info to add. Sorry I had to say it. :comm:

DrifterProdigy all dynos read differently you need to get some other people results from that dyno and see how they compare.

2slow240sx
07-26-2006, 04:32 AM
How about nitrous? How about fuel with a higher energy content than pump gasoline?


I limit my posts to things that are relavent to the topic. Since the original poster's car doesn't have nitrous, I saw no reason to include it into this equation.

Regardless, nitrous can't make a compressor flow more air. Read my post again to see the silliness of your comment.:26:

2slow240sx
07-26-2006, 04:34 AM
My friend made 325whp @ 18psi with a 10.0 AFR using a 2871R .64. He is on stock cams but has a Greddy Intake Manifold. I find it hard to believe that stock cams are restrictive to 330whp because once he gets his car tuned to 11.5 or better AFR, it will no doubt be at 350whp or over on the stock cams. Someone explain please? The power might be restricted with stock cams AND stock intake manifold to 330whp but i think if you upgrade the intake manifold, the added air will help achieve higher numbers even with stock cams.

Did you not read a single thing posted by Def about compressive fluid dynamics?

Jeff Taylor
07-26-2006, 08:41 AM
A turbo designed to flow around 36lb/min can't make over 400whp as a single turbo setup.
[quote=2slow240sx]

[quote=2slow240sx]Regardless, nitrous can't make a compressor flow more air.

Correct on the second part.

But a turbo designed to flow around 36lb/min could make over 400whp depending on what fuel is used. Pump gas? Probably not. C16? Probably. Methanol? Yes. Nitrous? Yes! Nitromethane? Yes!

_Def_
07-26-2006, 08:42 AM
Oh well, we got somewhere: we disproved the "330whp" rule.

It's not a rule, it's just the point where you *start* to choke the intake ports. It requires lots of pressure at that point to start to choke the intake ports for more and more of the intake duration.

Cylinder pressures are high when the intake valve first opens due to exhaust residual, especially on a restrictive turbine like this. So yes, you can get a tiny bit more flow by cranking up the boost, but all that's doing is incrementally increasing the flow by choking an additional small sweep of the crank angle.

Add cams and you now open the valve MORE, which gives more throat area(i.e. the choke point is much higher at the same boost) as well as keeping the valve open longer(more time you can add to the "choked" point when you get there).


Again, if you're going to "nitpick" what I'm saying, at least have a basic understanding of the concepts I'm using. You don't seem to know what I'm saying since the 330rwhp "choke point" seems to not go along with your tuner street cred or whatever. It's not a set in stone limit, and you can change the weightflow you choke at by changing the density of the air(temperature mainly), so yes you can make more power, it just gets very hard around that point because you are dealing with the intake ports being sonic for most their duration.

BTW - I notice lots of those dynos you linked to are on dynapack dynos, which I don't trust as far as I can throw 'em. Those things seem exceptionally easy to manipulate into giving "inflated" numbers. They can be accurate, but all too often I've seen things "played with" to inflate peak numbers.

_Def_
07-26-2006, 08:43 AM
Correct on the second part.

But a turbo designed to flow around 36lb/min could make over 400whp depending on what fuel is used. Pump gas? Probably not. C16? Probably. Methanol? Yes. Nitrous? Yes! Nitromethane? Yes!

Nitrous isn't a fuel - it's a chemical oxidizer...

b18c_ferio
07-26-2006, 09:01 AM
what effect would spraying nitrous at/in the air inlet/filter have on air flow/density?

Jeff Taylor
07-26-2006, 09:18 AM
Awesome. Now we're almost on the same page.

Jeff Taylor
07-26-2006, 09:24 AM
what effect would spraying nitrous at/in the air inlet/filter have on air flow/density?

An insignificant amount, unless you consider its cooling effects.

It does however effect the amount of oxygen in the combustion chamber, thus producing more torque.

SRENITY
07-26-2006, 10:40 AM
The think a few people here are thinking that us nay sayers are discrediting the tuning ability of YellowMunson. This is not the case at all he must be a fine tuner if he is a certified AEM tuner as shown on his signature. The point that we are trying to make is that no matter how good of a tuner you are you are not going to be able to change the laws of thermo dynamics/fluid dynamics. No body said it is not possible to make 400WHP with a GT28RS. We are saying that it is impossible to make 400WHP with the GT28RS with the conditions stated by the poster i.e. stock cams, no VE mods, pump gas mixture, no nitrous. YellowMunson: good tuner, not GOD.

2slow240sx
07-26-2006, 04:46 PM
The think a few people here are thinking that us nay sayers are discrediting the tuning ability of YellowMunson. This is not the case at all he must be a fine tuner if he is a certified AEM tuner as shown on his signature. The point that we are trying to make is that no matter how good of a tuner you are you are not going to be able to change the laws of thermo dynamics/fluid dynamics. No body said it is not possible to make 400WHP with a GT28RS. We are saying that it is impossible to make 400WHP with the GT28RS with the conditions stated by the poster i.e. stock cams, no VE mods, pump gas mixture, no nitrous. YellowMunson: good tuner, not GOD.


Very well said, sir.

Jeff Taylor: You keep adding different variables into the equation, then mixing it all up with my quotes. However, as I already stated, I have been using only the setup parameters in this particular scenario.

Yeah, sure, you can spray nitrous and increase the horsepower. Is it because you increased VE or mass airflow? NO. It's b ecause you added more oxygen (33% more by weight to be exact), thus requiring more fuel, resulting in a faster piston speed. And since horsepower is a factor of tq applied over time, obviously the hp number would be higher.

C16, methanol, nitromethane, etc. won't make this turbo flow more than it's able to flow. These fuels only provide a slower flamefront speed, resulting in the ability to run higher boost and more agressive timing. They do not magically pull some extra lb/min through a compressor that's already maxed out, incapable of pulling in more air.

Additionally, regardless of flamefront speed, once MBT is reached, that's it. There's no more. Period. Doesn't matter if you put solid rocket fuel in there.

You keep overlooking, as Def has already mentioned, that the small housing on the GT28RS is creating a ridiculous loss in VE, via high delta P across the head. Remember, the best numbers come when the delta P across the head is lowest. You can have an appopriately sized turbine housing that results in near equal pressures between exhaust and intake manifolds, since the turbine doesn't require high manifold pressure, but a high delta P across the turbine wheel itself.

In the end, I am happy with what I understand to be true, as it seems to work fine for me. I sleep at night, I'm sure this guy's car is very fast, and I'm sure you've built some impressive machines. Most likely, none of this is worth debating anymore.

Goofynick6
07-26-2006, 08:01 PM
You all should listen to Jeff. He knows a LOT more than most 240 owners. He ran a 7.3 in the 1/8th with his SR. He holds the record for 100% stock KA (527whp), and is a tuner for Ride Revolutions in TN. He made a COP setup using an SR ECU for his KA, who else has even thought of doing that?

The point is, he's not just some internet idiot trying to start fights and pick apart arguments semantically, he's trying to open people's minds to the fact that these engines aren't as limited as a lot of people tend to theorize.

I say take his advice and learn what you can.

Nick

_Def_
07-26-2006, 09:46 PM
You all should listen to Jeff. He knows a LOT more than most 240 owners. He ran a 7.3 in the 1/8th with his SR. He holds the record for 100% stock KA (527whp), and is a tuner for Ride Revolutions in TN. He made a COP setup using an SR ECU for his KA, who else has even thought of doing that?

The point is, he's not just some internet idiot trying to start fights and pick apart arguments semantically, he's trying to open people's minds to the fact that these engines aren't as limited as a lot of people tend to theorize.

I say take his advice and learn what you can.

Nick

Some of us are actually engineers who get paid to think about/test this stuff all day long, not just make power with an engine(that really only requires money and a little bit of knowledge, or can be done with just more money). I'm not saying he doesn't know about SRs/KAs/Nissans in general, but I'll put up my knowledge of fluid dynamics with anybody else on these forums.

dryft_s15
07-26-2006, 09:52 PM
At the end of the day, the theories have to be brought in line with the practical results, never the other way around.

fast_97_240sx
07-26-2006, 10:53 PM
^^^ so your saying DEF talks to much? Sorry types.

I still say my results R impracticle but solid.

Jeff has an Engineering degree from VT.

And I would put my knowledge of bodily excretions up against anyone on this forum.

Goofynick6
07-26-2006, 11:56 PM
That's great, but this forum isn't worried about who's better at fluid dynamics, it's about cars and their potential.

KB240SR
07-27-2006, 12:07 AM
Im curious what Fast 97's car will do on a Dynojet or Mustang Dyno since thats what the majority here uses. Also whats the choking point is for a stock intake manifold? Answering this will put my mind at rest over the whole subject.

Jeff Taylor
07-27-2006, 12:19 AM
Very well said, sir.



Yeah, sure, you can spray nitrous and increase the horsepower. Is it because you increased VE or mass airflow? NO. It's b ecause you added more oxygen (33% more by weight to be exact), thus requiring more fuel, resulting in a faster piston speed. And since horsepower is a factor of tq applied over time, obviously the hp number would be higher.



Yup, yup, and yup. But, please explain how nitrous increases the piston speed of an engine versus without nitrous?






C16, methanol, nitromethane, etc. won't make this turbo flow more than it's able to flow. These fuels only provide a slower flamefront speed, resulting in the ability to run higher boost and more agressive timing. They do not magically pull some extra lb/min through a compressor that's already maxed out, incapable of pulling in more air.


Yup, and yup. These fuels will not make the compressor flow more air, as you say. But will these fuels produce more power than gasoline with the same amount of airflow? Do these fuels possess a higher energy content than gasoline at their ideal AFR's? Yes. The following is a link you should look at. If you do not trust the validity of the data then I could upload several SAE journals in support of it. http://www.smokemup.com/tech/fuels.php (http://www.smokemup.com/tech/fuels.php)

Notice Table 1. Notice how the air flow remains constant. Notice the 27% and 136% differences in total thermal energy between gasoline and methanol and nitro methane, respectively. Do you still say that regardless of the fuel used, a given turbo cannot produce anymore than its output on pump-gas?






Additionally, regardless of flame front speed, once MBT is reached, that's it. There's no more. Period. Doesn't matter if you put solid rocket fuel in there.


Minimum Best Timing varies dependent on the fuel type. "Solid rocket fuel" will have a different MBT than gasoline. What's your point here?






You keep overlooking, as Def has already mentioned, that the small housing on the GT28RS is creating a ridiculous loss in VE, via high delta P across the head. Remember, the best numbers come when the delta P across the head is lowest. You can have an appopriately sized turbine housing that results in near equal pressures between exhaust and intake manifolds, since the turbine doesn't require high manifold pressure, but a high delta P across the turbine wheel itself.


I am certainly not trying to argue those facts. I am "overlooking them" because they do not need to be argued. I am, however, "nit picking" on your points that I feel are questionable or wrong.

I really do realize I'm coming across as an *******. It got everyone's attention, and that was my point. While my criticism seems harsh, it truly does have constructive undertones. As I kind of said earlier, we're all here to learn from each other, and if you can prove me wrong, I'd love to learn from your rationalization.

Jeff

Jeff Taylor
07-27-2006, 12:25 AM
And I would put my knowledge of bodily excretions up against anyone on this forum.

lol... I just now caught the fluid dynamics joke.

[/Humor] :D

Jeff Taylor
07-27-2006, 12:39 AM
Some of us are actually engineers who get paid to think about/test this stuff all day long, not just make power with an engine(that really only requires money and a little bit of knowledge, or can be done with just more money). I'm not saying he doesn't know about SRs/KAs/Nissans in general, but I'll put up my knowledge of fluid dynamics with anybody else on these forums.

You're an engineer? Wow. You must be right then.

I'm sure you know a lot more about fluid dynamics than me. Unfortunately fluid dynamics is only one facet of many involved in tuning an engine. Broaden your scope.

Nikeboy355
07-27-2006, 02:03 AM
I lost interest in this post now...

Jeff and his crew's posts are a little more bolder than they need to be...
Def is just questioning based on his experience and on scientific principles that he deals with everyday... I should also point out that he has been on these boards a very long time and has had nothing but solid advice/help...
and he has kept his posts quite professional...

I would be curious:
1. Why no other tuner has made this amount of power with that turbo...
2. What a compression test on that motor would come out to...
3. What another dyno would read...

and what Scott (Enthalpy) would say...

Goofynick6
07-27-2006, 02:49 AM
I lost interest in this post now...

Jeff and his crew's posts are a little more bolder than they need to be...
Def is just questioning based on his experience and on scientific principles that he deals with everyday... I should also point out that he has been on these boards a very long time and has had nothing but solid advice/help...
and he has kept his posts quite professional...

I would be curious:
1. Why no other tuner has made this amount of power with that turbo...
2. What a compression test on that motor would come out to...
3. What another dyno would read...

and what Scott (Enthalpy) would say...

Ahhh, a good ol' case of the "Who's been on the boards longest and has the highest post count" eh? I guess in that case I don't know much at all and should leave all the thinking and smart stuff to others and just go on my way quietly...

s14rhd
07-27-2006, 03:56 AM
and what Scott (Enthalpy) would say...

http://forums2.freshalloy.com/showthread.php?t=132466&highlight=STOCK+CAMS

2slow240sx
07-27-2006, 05:37 AM
Yup, yup, and yup. But, please explain how nitrous increases the piston speed of an engine versus without nitrous?

More fuel required to run the nitrous = more energy released = faster engine acceleration = high piston speed.







Yup, and yup. These fuels will not make the compressor flow more air, as you say. But will these fuels produce more power than gasoline with the same amount of airflow? Do these fuels possess a higher energy content than gasoline at their ideal AFR's? Yes. The following is a link you should look at. If you do not trust the validity of the data then I could upload several SAE journals in support of it. http://www.smokemup.com/tech/fuels.php (http://www.smokemup.com/tech/fuels.php)


Notice Table 1. Notice how the air flow remains constant. Notice the 27% and 136% differences in total thermal energy between gasoline and methanol and nitro methane, respectively. Do you still say that regardless of the fuel used, a given turbo cannot produce anymore than its output on pump-gas?

Very good link and table depicting the BTU's of each fuel. It was easy for me to associate power with airflow, forgetting that the airflow is only a medium through which the fuel can be spent, maximizing it's potential power.

That being said, I can see how using these alternative fuels would increase the amount of power made in the areas where the turbo CAN flow air, even though it runs out of flow later on, assuming the timing was appropriately adjusted for MBT (mean best torque). And since hp is a measure of tq applied over time, the increased amount of tq in the area in which the turbo CAN flow air would result in a higher overall hp output.


Thanks.





Minimum Best Timing varies dependent on the fuel type. "Solid rocket fuel" will have a different MBT than gasoline. What's your point here?

I was referring to Mean Best Torque. However, given my new understanding of fuel and it's potential power, I stand corrected on this statement, seeing as how the MBT (in my usage of the term) would be very much dependent on the fuel.







I am certainly not trying to argue those facts. I am "overlooking them" because they do not need to be argued. I am, however, "nit picking" on your points that I feel are questionable or wrong.


I really do realize I'm coming across as an *******. It got everyone's attention, and that was my point. While my criticism seems harsh, it truly does have constructive undertones. As I kind of said earlier, we're all here to learn from each other, and if you can prove me wrong, I'd love to learn from your rationalization.

Jeff

In closing, I have a better understanding of fuel and it's potential power, and for that I thank you.

However, I still believe the dyno numbers on this guy's car are a bit optimistic. I just don't see the mix of pump gas/C16 (a modest mix at that) used in this case was enough to bump the BTU's up so high that the engine made over 400whp. Regardless of fuel potential, the other issues remain (i.e. air flow limitation through the head, choking from the turbine housing, which results in lower VE, higher cylinder pressures, more reversion, higher cylinder temps, etc.).

Furthermore, regardless of claimed power output and all that's associated, track times never lie. I know that Bristol isn't one of the fastest tracks, but it's not so much slower that a 400whp/400wtq (or thereabouts) will run mid 12's, instead of the low 11's it SHOULD be running. Think about it. Bristol is quite a bit lower, in terms of altitude, than MANY of the other tracks, which consistently show faster times.

Yes, all of that is directly related to the driver, but it's my understanding that a professional driver drove his car down the track for him.

As I said a billion times already, I'm not saying this guy's setup sucks, the tuning was bad or that his car isn't fast. If I were in his shoes, I would have spent less time on this thread and more time out beating on it like a government mule.:D

fast_97_240sx
07-27-2006, 07:06 AM
Im curious what Fast 97's car will do on a Dynojet or Mustang Dyno since thats what the majority here uses. Also whats the choking point is for a stock intake manifold? Answering this will put my mind at rest over the whole subject.
We have never used the stock manifold.
It is a Dynojet 248 w/248awd . We've had several people that have used other area dynos and have made less power on ours.

& slow240

Bristol isn't slow due to altitude, it's slow because of track prep and the conditions of the air. It's down in a valley and there isn't much wind, very muggy. The car will go 11's there, the driver only made 2 passes that night due to domestic failures on the track. I can't go beat on the car right now with this tune in it We know that this it isn't a driving around tune. I stated before that I drive the car on around 310 maybe less.
You seem to have spent more time than me on this thread already.

BillKlineVT
07-27-2006, 10:30 AM
More fuel required to run the nitrous = more energy released = faster engine acceleration = high piston speed.Umm... acceleration != speed...

Correct me if I'm wrong, but only way to increase piston speed on the same engine would be to either rev higher, or to change the length of stroke (thus not really being the same engine anymore).

Sorry, had to join in on the 'nitpicking'. Continue on...

2slow240sx
07-27-2006, 03:26 PM
Ahhh, stinkin' definitions. You got me there, sorry. I meant the speed at which the piston accelerates, but it just came out as "speed."

That's the problem with proof reading your own material. You find yourself completing incorrect statements in your mind and don't catch it on the screen/paper.

I think it's time I go finish my engine and stop bothering about other people's stuff. I'll probably end up making like 300whp @ 20psi anyhow, making me feel like a big dofuss for posting anything on this thread.

2slow240sx
07-27-2006, 03:45 PM
One other note to Fast_97_240sx:

ALL YOUR BASE ARE BELONG TO US~!!!

_Def_
07-27-2006, 04:11 PM
Ahhh, a good ol' case of the "Who's been on the boards longest and has the highest post count" eh? I guess in that case I don't know much at all and should leave all the thinking and smart stuff to others and just go on my way quietly...

Ummm.. how about I control the flow through choked nozzles for longer than I'd care to each week. It's pretty easy to see what's going on when you've got a few hundred thousand dollars of data system sitting around you and you have access to about 3000 HP worth of compressor power. It does't take that much to make the "mental leap" and apply that to how THE VAST MAJORITY of SR20's seem to just "stop" at 330rwhp regardless of the turbo at around the most you'd really want to run on pump gas(17-20 psi).

Goofynick6
07-28-2006, 08:32 AM
Perhaps the majority, but not all. We're just saying that there's no need to put limits on engines, because they will always surprise you. Yes, there's room for improvement in the flow of the components, but there are so many factors determining the power output, that it's just one part of the equation.

forcefedS13
07-28-2006, 10:44 AM
Dyno queens get on my nerves. Lets see you drive it.
I dont like you Def: you're the rudest, most impatient person here.
I LOVE FRESH ALLOY.


But seriously, all jokes aside, no matter the arguement, or how you rationalize it, the DP made 400whp. Lets get over it, the numbers are there.

tErbobOOst
07-28-2006, 11:48 AM
Def is not rude. He knows his **** and gets pissed when others try to tell him he's wrong with no information backing it up except a link to some dumb ass website, like www.smokemup.com (http://www.smokemup.com) hahahahaha. Any website with a name like that must know their ****.

Engineers are not engineers because they can look at some books and use equations, or because they can use google as 50% of this board does. You must understand what is going on and why, and then use those equations accordingly. Def does this **** every day, both with personal cars, and for his job. I'm not sure what 2slow does, however he seems to know his ****, and just like def backs up everything with facts...something only def and 2slow has done thus far.

Your really going to go and tell us that this guy broke some of the fundamental rules in thermodynamics and fluid dynamics? You can only make so much power with a given amount of airflow. Doesnt matter how good the tuner is. I was not personally aware of the intake going sonic, however it does make sense (I am also a 4th year eng student), and would restrict airflow as def stated.

And that link with the fuel and how much power is made...that **** is such bull. According to that table if you ran a 6:1 afr on gasoline you would make more power than a 12.1 afr! There is WAY more that goes into power prodcution than how much fuel you put it, and how much energy that fuel has. Not to mention, this guy was running a mix of pump and C16...not any other fuel. So the fact that you can make more power on other fuel does not matter. And there is still a point where no matter what fuel you run there is no more power to be made due to the amount of airflow. The reason you can make more power with those methanol is because given an amount of air you can add more fuel as methanol has a lower stoicheometric afr...he wasnt using any special fuel, and was tuning at a normal AFR.

I've stayed out of this discussion because its ****ing stupid. He is not making that much power, period. He may be making more than average...but he is not making that much. Take it to another dyno and prove it. The dyno he is currently using has some of the settings wrong. Whether it be the load, elevation correction (there should be no elevation correction for turbo cars), or something else.

Not to mention the time and trap speed that he ran with that car. Time is very driver/track/launch dependant. But trap speed is fairly consistant with power. And your trap speed of 117 is coincidentally right around the 300-320 hp.

forcefedS13
07-28-2006, 12:13 PM
Calm down homer...no need to wig out. Notice i was joking about Def. "all jokes aside"anyway, why are you hating on a guy that just proved he made the power on a dyno. Would you like a written invitation to view the dyno run in person?Im not trying to start an arguement, but there is no reason to flip the **** out over something so stupid. He did it, the dyno shows it, why not be happy with the guy and congratulate him. If hes fulla ****, hes the one who has to deal with it.

tErbobOOst
07-28-2006, 01:17 PM
Calm down homer...no need to wig out. Notice i was joking about Def. "all jokes aside"anyway, why are you hating on a guy that just proved he made the power on a dyno. Would you like a written invitation to view the dyno run in person?Im not trying to start an arguement, but there is no reason to flip the **** out over something so stupid. He did it, the dyno shows it, why not be happy with the guy and congratulate him. If hes fulla ****, hes the one who has to deal with it.

Sorry, I didnt take your joke as a joke...it sound serious, I thought the joke was the "I LOVE FRESHALLOY" part. oops. doesnt change the fact that people are still trying to tell def and 2slow that they are wrong without backing it up w/ REAL information

I am happy for the guy. My first post in this thread was congratulating him on his setup, and me saying I'm sure its fast and a fun car. It pisses me off to see all these people trying to defend that he made that much power though, when its almost impossible. I'm not doubting he made it on a dyno...but you could dyno a stock KA24, mess with the dyno settings, and come up with a 400hp run...doesnt mean thats how much power its making. I'm not hating on the owner of the car, he seems to be a smart guy, that is taking this thread more mature than most trying to defend his power...and I'm most deff jealous of his setup.

As I said earlier...I just wouldnt wave those numbers around because they are most likely wrong. I'm sure he is making good power, hell anything over 300 on the street is almost useless. But hes not making that much power on such a small compressor, low boost, and stock cams.

_Def_
07-28-2006, 01:39 PM
Dyno queens get on my nerves. Lets see you drive it.
I dont like you Def: you're the rudest, most impatient person here.
I LOVE FRESH ALLOY.


But seriously, all jokes aside, no matter the arguement, or how you rationalize it, the DP made 400whp. Lets get over it, the numbers are there.

I feel the love, and 14 hr workdays do make me impatient. :26:

BillKlineVT
07-28-2006, 03:03 PM
Homer, funny how this thread was just dying off and you had to bring it back. Pretty hypocritical to call the thread bull**** if you're going to start talking **** to try to fuel the fire even more. Your posts in this thread have not helped at all and are just re-hashing information that has already been repeated numerous times in this thread.

P.S. You'd be surprised how many of the people participating in this thread have an equal or greater amount of engineering experience than yourself - they aren't just google searching newbs. I would like to believe that being an engineering student would prohibit you from making such poor assumptions, but what can you do. Def obviously knows his **** about thermo/fluids, that's been proven, and no one is discounting that fact.

Tough crowd on FA, jeez.

rs4race
07-28-2006, 03:05 PM
I love the tq on this dyno.

But just like the first reply on my dyno post of my gt2871r .64 this is all disbeleif too. I just like to think of it this way. Most of these e-bullies or e-thugs dont really know anything real. Most of their knowledge is just from what they have read on the internet and not from real world experience. Real world experience beats knowledge gained on the internet or theories. In my opinion.

Also I beleive its impossible for every part manufactured to be exactly the same. Is it possible that he could have gotten that one turbo that was made just better than whats rated?

Maybee a magical tank of gas, or a really nice tune. Maybee a really generous dyno?

If you look at his tq numbers they are all in the mid range. I would expect with stock cams it would drop off so low like it does in the high end. I would expect if he changed cams he would loose some of that mid range and gain a little bit of high end tq. I think that these results are possible.

Just my two cents

2slow240sx
07-28-2006, 03:30 PM
I'm not sure what 2slow does, however he seems to know his ****, and just like def backs up everything with facts...something only def and 2slow has done thus far.


I stayed at a Best Western last night!

forcefedS13
07-28-2006, 04:48 PM
Lol.

fast_97_240sx
07-28-2006, 09:40 PM
when its almost impossible.

But hes not making that much power on such a small compressor, low boost, and stock cams.

See there you even said that it's possible.

They aren't stock I said We switched to HKS 270 cams to get the power up.

I would love to dyno the car for anyone that would like to see it. I have nothing to hide and If I wasn't so damn poor I take it to another dyno and run it but I ain't got no green. You could PayPal me cash and I set it up somewhere else.
Chris

KB240SR
07-28-2006, 11:09 PM
Not to mention the time and trap speed that he ran with that car. Time is very driver/track/launch dependant. But trap speed is fairly consistant with power. And your trap speed of 117 is coincidentally right around the 300-320 hp.

Wont the trap speed also change with the launch and tires used? Ive only ran my car on stock tires at the track and can only get a best of 2.4 60ft with a time of 13.1 @ 113mph. When i would run a 2.5 60ft, my time was a 13.4 @ 112mph. Once the car hits boost, the tires are spinning all the way to 80mph in 3rd. With my times, it would seem as if i get drag radials to get traction, it would accelerate alot harder being able to gain a little more speed since i wouldnt be spinning much at all. Am I wrong?

Goofynick6
07-29-2006, 10:21 AM
...hell anything over 300 on the street is almost useless.

What? Are you one of those people that think a car with 250hp is "REALLY FAST!!"? Change that number to 600 and you're getting there.

The guys who run this dyno where this car was dyno'd are very good and have been doing it for years; they didn't get their jobs by being stupid. You "engineers" think you have all the answers, but there are so many variables involved that you can't possibly know what the results will be every time. I took 3 years of mech. engineering, so that means I'm 3/5th's of the way to being a know it all!

tErbobOOst
07-29-2006, 02:15 PM
What? Are you one of those people that think a car with 250hp is "REALLY FAST!!"? Change that number to 600 and you're getting there.

The guys who run this dyno where this car was dyno'd are very good and have been doing it for years; they didn't get their jobs by being stupid. You "engineers" think you have all the answers, but there are so many variables involved that you can't possibly know what the results will be every time. I took 3 years of mech. engineering, so that means I'm 3/5th's of the way to being a know it all!

Have you ever driven a car w/ 600 hp? I have, an AWD talon and it was ****in scary as ****. Now change that to RWD and you have a car that is completely unusable at full throttle. 250 hp is not REALL fast by any means, it is quick though. Anything over 350 hp and you start running into traction problems on the street. What use is that much power when you can only use it in 4th gear?

Couldnt make it through engineering?? :26:

I dont doubt that they are good. I never said anything about their tuning, I'm sure they know what they are doing and the car is making its maximum hp possible. But the power they are making is not possible. I said it is "almost" impossible to leave some room for error. It may be possible, but HIGHLY unlikely. Until he puts it on another dyno I'm content with knowing he doesnt have that much power.

I'm done. Good bye

rs4race
07-29-2006, 02:15 PM
haha hes right about it being almost useless. Its cause its so fast. You run through the gears to quick. In lower power cars its hard to get up to 120 or 130 but in a higher power car (at least in mine) its like cruising at 60.

rs4race
07-29-2006, 02:28 PM
Have you ever driven a car w/ 600 hp? I have, an AWD talon and it was ****in scary as ****. Now change that to RWD and you have a car that is completely unusable at full throttle. 250 hp is not REALL fast by any means, it is quick though. Anything over 350 hp and you start running into traction problems on the street. What use is that much power when you can only use it in 4th gear?

Couldnt make it through engineering?? :26:

I dont doubt that they are good. I never said anything about their tuning, I'm sure they know what they are doing and the car is making its maximum hp possible. But the power they are making is not possible. I said it is "almost" impossible to leave some room for error. It may be possible, but HIGHLY unlikely. Until he puts it on another dyno I'm content with knowing he doesnt have that much power.

I'm done. Good bye

Dude I have a 400hp 240sx and I dont have any problems with traction. Thats well over 250hp. It helps if you have correctly sized tires. Im sure the mustang cobra is useless? Howabout the Corvette or viper? I know they dont have 600hp but they are well over 250hp.

If your going to make a 600hp car you need to adress the traction. I did that with mine... Full suspension, z32 brakes, and 275's in the rear and 255's in the front. I have plenty of traction.

Goofynick6
07-29-2006, 03:25 PM
My turbo M3 makes 400wtq and 375whp, and I can barely break traction in 2nd. My buddy's 650whp SR20 was a bit much on the street, but that was a 2500lb car too. 250hp is nothing if you ask me; I think minivans come with that much now.

KB240SR
07-29-2006, 07:02 PM
yea, tire size and compound definitly make the difference as far as power and traction. Im running stock all seasons which i spin to 50mph at 12psi and spin to 80mph at 19psi. I still wouldnt call it useless power, you just have to drive more careful.

s14rhd
07-29-2006, 09:36 PM
Dude I have a 400hp 240sx and I dont have any problems with traction. Thats well over 250hp. It helps if you have correctly sized tires. Im sure the mustang cobra is useless? Howabout the Corvette or viper? I know they dont have 600hp but they are well over 250hp.

If your going to make a 600hp car you need to adress the traction. I did that with mine... Full suspension, z32 brakes, and 275's in the rear and 255's in the front. I have plenty of traction. Do you hook up in 2nd? I have about 320whp and I can't get 2nd to hook on anything less then perfect roads. Have 9in rims with 235's what size rims are you using?

rs4race
07-31-2006, 02:11 PM
Yes I hook up in second. I used to always break the tires loose in second and chirp in 3rd.

i have 17x9 w/ 255 40 17's in the front and 17x10 w/ 275 35 17's in the rear. Traction is alot better now, although sometimes it does break loose in the upper rpm's of first and second.

s14rhd
07-31-2006, 08:31 PM
Would think it would be worth my while switching up to 255's from my 235's? I like to corners as well.

TS4l
08-01-2006, 12:32 PM
I'm using the Azenis 615's in 245/45/17 with about 400hp and they hook pretty good. I lose traction at the top of first and sometimes 3rd and 4th but they hook really good for their size. I had some other brands in the same size and these are a lot bigger and have way more traction than all the others I've used. They are also very consitant about when they break lose which I like going into corners rather than my old tires that randomly would lose traction. Just my 2 cents.

_Def_
08-01-2006, 02:59 PM
Keep in mind that these taller tires you guys keep mentioning reduce your drivewheel torque in each gear by the percentage gearing change due to the larger diameter. That goes a long way towards making a tire more compliant in straightline traction in the lower gears, because you're effectively putting a taller rear end ratio on the car as well as giving it a sticky tire to work with.

My 275/40-17's don't really spin even with 19 psi boost spikes in 2nd, but that's mostly because they make my gearing super long compared to something like a 235-245/40-17.

s14rhd
08-01-2006, 09:34 PM
Keep in mind that these taller tires you guys keep mentioning reduce your drivewheel torque in each gear by the percentage gearing change due to the larger diameter. That goes a long way towards making a tire more compliant in straightline traction in the lower gears, because you're effectively putting a taller rear end ratio on the car as well as giving it a sticky tire to work with.

My 275/40-17's don't really spin even with 19 psi boost spikes in 2nd, but that's mostly because they make my gearing super long compared to something like a 235-245/40-17. There wider not taller?

2slow240sx
08-01-2006, 09:38 PM
Yes, they're taller. The /40 number is a percentage, so as the tire widens, while the percentage remains the same, the actual dimension changes.

_Def_
08-01-2006, 09:40 PM
This link explains how to read a tire size:

http://www.teammiata.com/libs/tire-sidewall.htm


The larger the section width with the same aspect ratio means you end up with a larger diameter tire, which affects your overall gearing.

s14rhd
08-01-2006, 11:59 PM
Cheers