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DETeatsvipers
05-06-2003, 07:58 PM
Ive never seen a post on this before, anyone have any input.

Brad
05-06-2003, 08:03 PM
ive only seen turbo/nitrous combos on cars with huge ass turbos to reduce turbo lag

DETeatsvipers
05-06-2003, 08:08 PM
exactly

Refill
05-06-2003, 08:20 PM
I hope to run some Game Genie on my SR later this summer, I'm sure lots of other people have tried it.

**DONOTDELETE**
05-07-2003, 02:31 PM
While not exactly commonplace it's not that unusual to see SR's with relatively small turbos running gas in aus. Generally it's used by those who want to be semi competitive at the strip while retaining a very driveable streetcar. Best example I can think of is an S15, rocker cover never opened, standard turbo running high 11's on slicks with a 50 shot.

Irie_eyes
05-08-2003, 03:33 AM
I posted this a while ago but the wrong place (Car Lounge).
Any thoughts about injecting nitrous into the turbine, so a pre-turbo injection setup? I'm say dry since wet would be kinda catastrophic. Any scientific issues with injecting a liquid gas that is expanding?

WRX_XRW
05-08-2003, 09:31 AM
Wouldnt the turbo compress it and shot twice as much in?

flip240
05-08-2003, 09:48 AM
Wouldnt the turbo compress it and shot twice as much in?



What?! LOL!!! http://forums.freshalloy.com/images/graemlins/grin.gif

SilviaDET
05-08-2003, 10:05 AM
I think a wet system would be prefered, due to the fact that you don't want to run your car rich all the time, and if you just added a dry system without adjusting the fuel pressure you would be running very lean while spraying.

Now, does anyone make a nitrous controller that will automaticly cutoff when 8lb's or so of boost is attained? So you can use the nitrous specificly for anti-lag.

asad
05-08-2003, 10:23 AM
I think a wet system would be prefered, due to the fact that you don't want to run your car rich all the time, and if you just added a dry system without adjusting the fuel pressure you would be running very lean while spraying.




How many times do I have to say this???

There seems to be a common misconception about dry nitrous systems not adding any additional fuel -- THIS IS FALSE.

Dry nitrous systems DO add additional fuel by raising fuel pressure while spraying through the use of a fuel return line restrictor.

Arguably, for low-hp nitrous shots this may in fact be BETTER than a wet system since the fuel, being delivered by the stock injectors into each port, will likely be more evenly distributed.

Asad

**DONOTDELETE**
05-08-2003, 11:38 AM
First off....the nitrous would lose it's fun loving powers because A, its gonna lose thermal power (its temperature which is cold) running through the turbine...as well when it is in the bottle is much more compressed that a turbo could re-perform, going from the bottle to atmosphere, it would give a cooling energey, but quickly be eaten up the the comprosser and associated housings. If you are trying to cool the turbo and the exaust (why in the world would someone do that) you should look into a funny little thing called overlap.

Nirtous + recompresion will not equal more nirtous, this is physically improssible, as much nirtous as you put in one side, the same you will get out, yes it will be compressed, but there will not be more, as well a significant loss in potency.

Spearco/Turbonetics makes boost sensitive switches.

Ok now ASAD, usually im in pretty good agreeance with you but, change of fuel pressure suddenly while (racing) under load....this dosent sound good. Ok, you up the fuel pressure, which is either going to give you more fuel per duty cycle or lack of a duty cycle all together(over 70psi injectors no longer want to close). But when the computer catches this problem (rich) from sudden raise in F/P it will lean back out. Now you can say, well the nitrous is going to match it, so the a/f will read a close to stoich reading, that would be nice, but if that were the case we could simply shoot the nitrous and wait for the ECM to increase duty cycle to go from lean to stoich.

Whats my point. Laws of fuel injection. NO sudden jumps in fuel pressure will be allowed by an ecm with a knock sensor and a/f meter.

But.... you might be right, Truthfully i have never seen a dry shot system in my whole life so flame away, (or maybe because I refuse to touch that kind of crap) but this is a better reason to either get a direct port or what i would call a dry shot + an HKS AIC with injector, all running off an independant fuel cell, now that would be tits.

YOU CANNOT CHANGE FUEL PRESSURE>

John von Endorphin

Kookz
05-08-2003, 12:02 PM
The ECU doesn't know the fuel pressure, which is why rising rate FPRs work.

cdn_w_sr20
05-08-2003, 12:26 PM
My problem with dry kits is simple, idiots put them on there car and blow their engines up for a good reason. Dry kits do not add to the potential of your engine, they max your injectors potential out. If you have 370cc injectors and your making 240rwhp and want to get to that 300rwhp level then your already hooped. I've always been pro to wet kits since they are safer, and add to the potential of your cars engine.

In other words, if you have a stock SR with FMIC, 3" dp and things like this and want that 300rwhp a wet kit can easily get you there.

Evil_rps13
05-08-2003, 12:51 PM
The ECU doesn't know the fuel pressure, which is why rising rate FPRs work.


you beat me to it,lol.However dry systems are good for small shots up to about the 65 range,although you can have them larger than that, they are just dangerous.I prefer a single wet fogger.Direct port is the way to go,you just can't get it that small.AFAIK, you are not using the o2 at wot anyway.

cdn_w_sr20
05-08-2003, 12:56 PM
You can make direct port for smaller amounts these days. NOS came out with these injector holders, not sure if they are for top/side feed or for both. Your injectors go right into them. The injector holders then add in fuel and nitrous into your fuel ports on your intake manifold. NOS says you can have as low as a 40 shot.

Evil_rps13
05-08-2003, 01:24 PM
You can make direct port for smaller amounts these days. NOS came out with these injector holders, not sure if they are for top/side feed or for both. Your injectors go right into them. The injector holders then add in fuel and nitrous into your fuel ports on your intake manifold. NOS says you can have as low as a 40 shot.


No kidding, thats pretty cool.It's about time.

**DONOTDELETE**
05-08-2003, 01:37 PM
Maybe you didnt read my post correctly, ECM will see the change in A/F (rich) and step down the duty cycle to accomodate for the raise in fuel pressure. It dose so by

ECM- Condition Rich (15.5
ECM- Action Step down (Safe mode
ECM- Condition Lean (14-14.2
ECM- Raise Duty cycle
ECM- condition stoich 14.7

It does this in a matter of 1-3 seconds. When it sees the rich condition it steps down the duty cycle tooo much to comply with emitons, this huge step down is like a bog or a hiccup. It then takes another second to recorect. Yes it will even itself out...but rememebr that the A/F and ECM will not read all of the burnt nitrous as O2. In turn you will not have an actual stoic reading. You will need a Lambda with a more advanced spectrum to correctly read burnt nitrous.

This is why im saying the dry does not work, the ecm A bogs, and B does not correct for the full mixture. Which equals = LEAN

YOU DO NOT CHANGE FUEL PRESSURE UNDER LOAD IN A RETURN SYSTEM FUEL INJECTION. Why does that not make sense?

A rising rate FPR works because it changes fuel in increments, not a switch from 40 - 60 psi.

John von Endorphin
Builtperformance@mail.com

gatecrasher
05-08-2003, 01:55 PM
I think a wet system would be prefered, due to the fact that you don't want to run your car rich all the time, and if you just added a dry system without adjusting the fuel pressure you would be running very lean while spraying.




How many times do I have to say this???

There seems to be a common misconception about dry nitrous systems not adding any additional fuel -- THIS IS FALSE.

Dry nitrous systems DO add additional fuel by raising fuel pressure while spraying through the use of a fuel return line restrictor.

Arguably, for low-hp nitrous shots this may in fact be BETTER than a wet system since the fuel, being delivered by the stock injectors into each port, will likely be more evenly distributed.

Asad




Fuel pressure isnt increased by using a restrictor in the fuel line. The "fuel" solenoid uses pressure to alter the signal to your fuel pressure regulator.

Dry systems ARE in theory better for a number of reasons. one being that you can make more power with a dry system since spraying only N2O into intake requires less "space" than the N20/Fuel mixture. Even large HP dry nitrous systems work well, provided you have enough fuel injector to support it. That is the reason wet kits are sold by manufactures for factory turbo cars......so that the stock fuel injectors arent being pushed further.

asad
05-08-2003, 02:02 PM
Maybe you didnt read my post correctly, ECM will see the change in A/F (rich) and step down the duty cycle to accomodate for the raise in fuel pressure.



Wrong WRONG WRONG!!! At WOT (the only time nitrous will be in use), the ECU ignores the O2 sensor COMPLETELY. It reverts to its fixed fuel and timing maps.

As for injectors not closing...well, who cares if they don't close? If you want safe, then let 'em dump as much fuel as they can. If you're running a small dry shot, clearly making huge power isn't the concern.

Asad

**DONOTDELETE**
05-08-2003, 02:02 PM
The pressure is higher comming from the bottle out of the nozzle than the boost or atmospheric pressure in the pipe, so the act of spraying only compresses the said air you are spraying into. As well you are not losing any O2 because the nitrous is a direct replacement. Where are you comming from.

asad
05-08-2003, 02:04 PM
Fuel pressure isnt increased by using a restrictor in the fuel line. The "fuel" solenoid uses pressure to alter the signal to your fuel pressure regulator.




Ah, sorry for the misinfo -- at any rate, the end result is the same: fuel pressure goes up, more fuel through the stock injectors.

Asad

primeral
05-08-2003, 02:18 PM
http://www.imagestation.com/picture/sraid14/p5ed634b5ff627bfcfaa0d491b5375001/fde14054.jpg

http://www.imagestation.com/picture/sraid61/pb14e5309f6a5e11066ee7602fb387814/fc35cff6.jpg

http://www.imagestation.com/picture/sraid61/p86f39895da36ed162af5059017246e62/fc3a9887.jpg

cdn_w_sr20
05-08-2003, 02:21 PM
Dry is still more dangerous unless properly tuned. Using additional fuel from your injectors is like letting a kid with matches and dynamite. Especially when your average import guy doesn't know a heck of a lot about nitrous in the first place. That is why I say the new NOS injector holders are the way to go. I will try to find some info out on them and post it up. They make fogger nozzles look 50 years ancient.

ADAM HUTCHINSON
05-08-2003, 02:31 PM
i agree dry is not the way to do it right...wet is the way to go and tune the system correctly http://forums.freshalloy.com/images/graemlins/smile.gif

http://www.turbo240sx.ca/noslines.jpg





Dry is still more dangerous unless properly tuned. Using additional fuel from your injectors is like letting a kid with matches and dynamite. Especially when your average import guy doesn't know a heck of a lot about nitrous in the first place. That is why I say the new NOS injector holders are the way to go. I will try to find some info out on them and post it up. They make fogger nozzles look 50 years ancient.

cdn_w_sr20
05-08-2003, 03:21 PM
Here's the shyt. You want nitrous do it the right way. Unfortunately you'd need a top feed rail for this. But this is the simplest way to make a Direct Port setup that practically anybody could do.

http://www.holley.com/HiOctn/ProdLine/Products/NOS/NOSNS/NOSzle.html

Site says 50hp+ shot. That and no fogger nozzles sitting all over the place...

DETeatsvipers
05-08-2003, 03:29 PM
i like vegtables too

pampadori
05-08-2003, 05:16 PM
good lord!
i run a dry 55shot. my fuel pressure goes up as soon as the kit starts spraying. my kit uses bottle pressure (which is often over 900psi) and sends some of that pressure to the fuel pressure regulator. (there is a jet in the vac hose so no, not 900psi is sent. more like 20psi)
asad of course, as most always, is correct. the ecu goes into closed loop at wot, and when rpms are above...3000k rpm asad? the ecu will go by maf signal to choose which fuel and timing maps it uses. there are many many maps stored in the nissan ecu's. this is also what the safc does to alter fuel. it will alter the maf signal so the ecu chooses maps that are actually supposed to be used at other maf voltages. ....no o2 sensor being read. now, the safc will work on light loads and low rpm also, but its my opinion that the ecu will "learn" this because the o2 sensor. so i periodically reset the ecu to combate this. maybe it helps, maybe not.
but dry n2o is okay unless you have a heavily modded engine in my opinion. i'm upgrading to wet for the racecar.
shaun
www.jgycustoms.com (http://www.jgycustoms.com)

DETeatsvipers
05-08-2003, 05:49 PM
oh oh oh ok let me get this straight...

Your saying with my modified t25 hybrid turbo(turbonetics compressor wheel/modified exaust housing/wheel), runing .86-.93 bar approx thru the gears with stock 370 cc injectors and a nismo fpr with fp with vacum line connected set at 50 psi, and the afc richened up 10% over stock, with a mines or central20 ecu tuned for 1 bar with stock injectors/timing/turbo, and the base timing set at stock, i can run an additional 50 shot dry system in my system and i wont lean out. you guys are on crack. im already pinging at 14 psi of boost on 91 octane with nos octane booster. Yes when i run c16 i dont ping until 18 psi but comon now this is a street setup.
also how in the living fuc is the nos system goin to increase my fp any more!!! 50 psi at idle!!! wtf is it goin to do? the pump maxs out at about 70 psi. with a 1 : 1 boost reliant ratio ill be at about 63-64 psi of fp when racing under boost! my setup is maxed out. i guess what im saying is i already decided when i first posted that if i ever do a nos setup on one of my motors with a similar setup as above i will use a wet system, very small 35 shot , 50 at most i was just curious if anyon else has had good results or any major time drops in the 1/4 thanks to it.

cdn_w_sr20
05-08-2003, 06:35 PM
I ran a single fogger with my near stock setup and made 306rwhp with a 75 shot. I was make 257rwhp with my near stock setup with an S14 T28. I also had a FMIC (cheap starion) 3" DP, 3" exhaust and so forth. The duty cycle at 257rwhp was 94% and I wanted the 300whp level. Easiest way to do this was to obviously add a WET system.

This is why wet systems are the way to go. They add potential to your engine. If you are like me and you pick up nearly 50whp you could probably see 1/4 second off your time, maybe more all depending on how good a driver you are. If you use a wet kit the minimum you'll want to use is a 50shot likely. I tried playing around with jet sizes and such trying to start small. I noticed using a 35 to 40 shot didn't produce anything you could feel in the car. When I pumped it to 65shot i made 49whp and could feel the car pull hard when it kicked in.

DETeatsvipers
05-08-2003, 06:42 PM
what system did you use? so you used a 65 shot wet right before the throttle body? let me know how you set it up. i was thinking about a 50 shot at most.

cdn_w_sr20
05-08-2003, 07:45 PM
Not right before the throttle body, maybe a few inches. I had a between the throttle body adn where my IACV connection was. Just a single fogger system nothing extremely fancy. Can't remember the size of jets I used for it, but it should work well. And yes it was a wet system. I put a tee off of the line coming out of my fuel filter, easiest way to do it i think.

**DONOTDELETE**
05-08-2003, 10:41 PM
You had you're injectors at 94% duty cycle? How'd you do that? I want to know so i can do it too with out them staying open. It's a problem i've been having.

You intercepted the fuel send before the rail? You're injectors must love you for that.

cdn_w_sr20
05-08-2003, 11:39 PM
You cane make your side feeds go static if you really want, I wouldn't recomend it. My new system uses no nitrous though, make my engine make the power the good old fashioned way, Lots of Boost!

pampadori
05-14-2003, 12:06 AM
oh oh oh ok let me get this straight...

Your saying with my modified t25 hybrid turbo(turbonetics compressor wheel/modified exaust housing/wheel), runing .86-.93 bar approx thru the gears with stock 370 cc injectors and a nismo fpr with fp with vacum line connected set at 50 psi, and the afc richened up 10% over stock, with a mines or central20 ecu tuned for 1 bar with stock injectors/timing/turbo, and the base timing set at stock, i can run an additional 50 shot dry system in my system and i wont lean out. you guys are on crack. im already pinging at 14 psi of boost on 91 octane with nos octane booster. Yes when i run c16 i dont ping until 18 psi but comon now this is a street setup.
also how in the living fuc is the nos system goin to increase my fp any more!!! 50 psi at idle!!! wtf is it goin to do? the pump maxs out at about 70 psi. with a 1 : 1 boost reliant ratio ill be at about 63-64 psi of fp when racing under boost! my setup is maxed out. i guess what im saying is i already decided when i first posted that if i ever do a nos setup on one of my motors with a similar setup as above i will use a wet system, very small 35 shot , 50 at most i was just curious if anyon else has had good results or any major time drops in the 1/4 thanks to it.



crack? nope. sounds like your motor might not take it then. but you are using a mines computer. its my opinion, and experience that the mines ecu makes less power then the stock ecu. i used one for a while, and it made a noticably smaller amount of power. so we reprogramed the eproms with our speacial blend of guess work. made 304rwhp on a buddies car with it.
i'm using the stock fpr and running 20psi of boost with my 55shot. i get awfully rich when the n2o comes on. this is on 92octane. no pinging.
i agree that wet is better. but a dry shot will do with a lightly modded motor, given you don't run more then a 50shot. if you try to make 350hp with the 370cc inj and n2o, then yeah, dry isn't going to do great. but 300hp it will do. my walbro sends more then 70psi though.
in a pinch, use dry or wet. got more time and loot, go wet.
shaun

Kookz
05-14-2003, 03:13 AM
Just remembered a little something...

It's best for cooling to use the nitrous (or water, alcohol, whatever) as close to the TB as possible. This is because things cool at a rate proportional to the 4th power of the temp (T^4).