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flaSR20DETpower
03-17-2003, 12:03 PM
When im building up my turbo car I have everything pretty much down pat except for the fuel area. Im going to get an unstable hybrids fuel rail with the 50lb injectors and connectors in it already. I don't plan on running extremely high boost right away but I would like to get the right things first. What other things should I get. Its going to run on a JWT ecu and a S-AFC. I hear a lot about FPR's, would anyone care to explain to me about them...which ones are good and what kind I should look for. Also what about new larger fuel filter(maybe a z32) and fuel pumps. This is the last area I need info on and im kind of stuck with the configuration. any help would be appreaciated, thanks

handiman15
03-17-2003, 12:15 PM
I would upgrade the fuel pump to a z32 TT pump or an intake walboro fuel pump. If you want to, you can always get a in line fuel pump, bosch or something like that. I would get a rising rate fuel pressure regulator. Something that rises when the boost rises. I would also get the upgrade for the z32 MAF, it's well worth the money. Hoped this helped out a little.....

orion
03-17-2003, 01:34 PM
No need for an FPR with the JWT setup...or a properly tuned AFC for that matter. A 'rising rate fuel pressure regulator' is only good for pushing more fuel through smaller injectors - If you have bigger injectors, you're set. So forget about the FPR...

Fuel pump is not a necessity on an S14 for lower boost, but it's cheap insurance - And if you're planning on enough boost to warrant 50lb injectors, it's absolutely needed. I like the Walbro, and one company has an S14 fitment...

Fuel filter - The OEM one will do, but the S-chassis replacement costs $2 more the the 300ZX TT, and the Z32 filter has more capacity for flow, so why not?

Later - Brian

s13silady
03-17-2003, 03:15 PM
sorry to steal the post... but i will be running a RRFPR with the stock 270cc injectors.. will this be ok?
i plan on getting the 370CCs next month or so...will the RRFPR be ok with the 370's? or will i have to tune the 370's with the S-AFC?

orion
03-17-2003, 03:45 PM
RRFPR and 270s is OK for cheap option...

370s will need at least an ECU retune, S-AFC, or hacked MAF. I'd reccomend them in that order...

370s and an RRFPR is too much - Just 370s and an AFC should get you to 10psi with no trouble, assuming you can tune it properly.

I'd say skip the RRFPR and buy the 370s now, and get the retune or the S-AFC. Should be good to about 260-280rwhp.

Later - Brian

flaSR20DETpower
03-17-2003, 03:54 PM
I was going to get the ECU before the safc. I am going to use a blow through Cobra MAF...

Rownan
03-17-2003, 04:35 PM
JWT is good for a reliable setup but the S-AFC will allow you to tune yourself. That may or may not be a good thing. Good if you know what your doing or know someone who does.

orion
03-17-2003, 05:17 PM
flaSR20DETpower -

Good call - I like that setup...and eventually I will do the same.

You'll have to change your screen name to flaKA24DETpower...hehe!

And as Rownan said - AFC could still be useful for tuning (there is power to be found in a JWT setup), but at the expense of some safety - Only use it with a wideband, on the dyno would be best.

Later - Brian

flaSR20DETpower
03-17-2003, 06:48 PM
yes I will have to change my screename. When I first got into 240s I wanted a SR20....... but for the same price of a SR swap I could be making more HP on my KA24 with some better parts =). Plus it has more displacement so turbo theoretically would spool a tad quicker and more HP output. Also all the parts are in the US..... I see the light now, at the end of the light is a KAT hehe

McGuirk
03-17-2003, 07:55 PM
Woot Woot, I know what you mean i am going KAT with an S14A. What type of turbo do you guys plan on using and what is your main objective (1/4 mile, auto-x, high hp, etc.)?

orion
03-17-2003, 09:01 PM
matt0491 -

I have already done my KA-T...

Objective is auto-x and road racing, and my goal was over 200rwhp at less than 6psi. That kind of power makes the S14 competitive with MUCH faster cars I've learned...

I am running T3/T04E, no intercooler, TiAL wastegate (dumped), 2.5" downpipe and exhaust, 370cc injectors, hacked MAF, S13 cams, 1G DSM BOV...

Made 224rwhp and 229rwtq at .4bar (5.8psi)...

I am pretty happy with it, after some 'growing pains' in the beginning (detonation killed my #4 cylinder - Too much timing, among other things).

Anyway, enjoy!

Later - Brian

AceInHole
03-18-2003, 12:08 AM
I am running T3/T04E, no intercooler, TiAL wastegate (dumped), 2.5" downpipe and exhaust, 370cc injectors, hacked MAF, S13 cams, 1G DSM BOV...


still no IC eh?? I'll have a 1G dsm sidemount on my car by the end of the week... should be finishing the engine install tomorrow or wednesday.

Anyways, my setup is the hacked MAF, 370cc injectors, no intercooler (for now), stock cams, stock exhaust, 2.5" downpipe. I was running 7psi when oil problems destroyed my engine.
[url=http://www.engr.uconn.edu/~corrales/240/engine_swap/part_III/oilpan001.jpg]Here you can see the destroyed rod endcap[/url

pasha
03-18-2003, 12:45 AM
sigh... so sad to see motors die.

btw, whats a hacked maf? how do you hack it? why do you hack it?

2shortysx
03-18-2003, 01:24 AM
matt0491 -

I have already done my KA-T...

Objective is auto-x and road racing, and my goal was over 200rwhp at less than 6psi. That kind of power makes the S14 competitive with MUCH faster cars I've learned...

I am running T3/T04E, no intercooler, TiAL wastegate (dumped), 2.5" downpipe and exhaust, 370cc injectors, hacked MAF, S13 cams, 1G DSM BOV...

Made 224rwhp and 229rwtq at .4bar (5.8psi)...

I am pretty happy with it, after some 'growing pains' in the beginning (detonation killed my #4 cylinder - Too much timing, among other things).

Anyway, enjoy!

Later - Brian




can you elaborate on some of the things that you learned? just curious to hear some stories and to name a few cars that were competitive.

Ozone
03-18-2003, 01:26 AM
Brian, what was the timing issue? Did you advance the timing when you were n/a and didn't bring it back when you went turbo? Or is the stock timing too much for turbo duty?


kevin

ninety_six
03-18-2003, 01:28 AM
it's basically a piece of PVC piping cut out to fit the stock element sensor...just means the sensor can measure more air, therefore telling the ECU to send more fuel via the 370cc injectors...the diameter of the pvc is a direct variation of the volume increase of the injectors...i believe the ideal size came out to be like 2.98 Inner Diameter (ID)....search for some of orions and AceInHole's previous posts, there are at least a few threads floating with countless info on this subject...

pasha
03-18-2003, 02:31 AM
thanks dood

orion
03-18-2003, 03:13 PM
ninety_six -

The hacked MAF is kinda the opposite - It sneaks more air in the engine to compensate for too much fuel from bigger injectors. If you just drop 370s in the rail, you get ~37% more fuel then needed, so you need to do something to get a comparable amount of air in there to get a proper A/F ratio. SO if you increase the cross sectional area of the MAF by same amount as the percentage increase in fuel, it almost evens out - And the theoretical ideal inner diameter (ID) of the new, bigger pipe would be 2.9" for a KA with 370cc injectors - I use exhaust tubing with a 2.875 ID and found it to be nice and rich, but safe.

2shortysx -

I compete locally against a Supra TT Auto with Hoosiers and a 2000 Cobra with 275 Victoracers in Solo II, and have found that I'm on the Supra's ass, and 1-1.5 seconds behind the Cobra. Race tires would make a roughly 5% difference in times from my experience, meaning I could be ahead with some R-compounds. And in the road racing experience I have, I have been not too far behind 2 of our local MKIV Single Turbo Supra 6-speeds - they run :59-1:02s on the Gainesville Raceway short course, and I ran consistant 1:05s when I was N/A (157rwhp) but at a recent Solo Trials evets on the same course, I ran 60.1 seconds with the turbo KA. On that day, though, one of the Supras ran in the :58s, so they are making improvement as well...

Ozone240 -

The timing issue was that I was still running a JWT N/A ECU upgrade with advanced timing...I backed off the static timing, but apparently not enough - I had some mild detonation after a 19psi boost spike, coupled with a loss of 2 quarts of oil (pressurized turbo oil return line), and a few 7000rpm shifts, all of which combined in killing #4. Had 30psi of compression in it, ~180 across the others.

Later - Brian

d240t2
03-18-2003, 05:02 PM
I backed off the static timing, but apparently not enough - I had some mild detonation after a 19psi boost spike



Detonation at 19psi on pump gas with 370cc injectors doesn't sound like a timing issue to me. That sounds like a fuel issue.

orion
03-18-2003, 05:42 PM
I wrote that wrong...

2 different events:

1) Boost spike to 19psi on a Wed night when installing my MBC - Hooked it up to the top port on the TiAL, as the instructions said (which went against instinct), and it spike to 19 as I let off. Corrected the install and it fixed the boost @ ~5.8psi...

2) The next night it actually broke - I think the piston may have sustained damage due to the spike, and then a litle too much timing gave way to a little detonation which finally broke the piston ring land loose.

Sorry for the confusion... - Brian