turbomax97

iTrader: (6)

What fuel pressure are you guys with 555cc injectors running at.... i.e. at idle, and at whatever boost you are running.... Also, relate the corresponding a/f numbers.....

crewchief264

I run the stock about 35psi @ idle and @ wot no more than 65psi I am on emanage no fmu.

slimer

iTrader: (13)

I am running 33 psi on 410 injectors with a 4:1 fmu disc. I have not seen more than 57 psi.

jcy98maxse

iTrader: (8)

David from deatschwerks is sending me some 500cc's he thinks it'll run just as good or better than Mike's 555cc's setup (in terms of being leaner). I'll be running SAFCII/A32 ecu/Z32 MAF/AFPR/500cc. Now I also have an FMU which was Mike's and it came with a 10:1 which I think I will need to get a smaller disk if I end up running it but I'm not gonna install it unless I have to.

slimer

iTrader: (13)

umm, you may need a 4:1 or 3:1, but you may not. good luck.

jcy98maxse

iTrader: (8)

yea I dunno wat the A/F would look like so I plan to get a wideband o2. My question is, should I have a higher fuel pressure and do (-%) correction under 10% on the SAFC (which I've seen many do) or should I go with a stock/slightly lower FR and add (+%) on the SAFC?

slimer

iTrader: (13)

as long as you are within +/- 10% you should be fine. I personally would like to subtract fuel, but thats me.

Shadow

iTrader: (15)

660cc injectors, 24psi at idle. Under full boost, car is tuned to about 11/1 AF on a dynojet. I'm sure on the street it's a little leaner. I've never paid attention to the FP gauge under full boost anymore since there is no FMU in the car now.

hlh0501

iTrader: (1)

That idles well? It's a common misconception people with big injectors have. Because they are at minimum pulsewidth and still have too much fuel at idle, they assume lower FP will fix it. This only seems to help down to around 33-35psi. Below that fuel won't atomize properly, and they end up with a junk idle again.

I thought that was universal, but maybe the difference in injectors is giving you better luck!

I30tMikeD

iTrader: (8)

50 psi at idle, 60psi at WOT. 550cc injectors. high 10's-low 11's on the stock ECU. Mid to high 11's on the JWT ECU

I30tMikeD

iTrader: (8)

If your running stock timing your better off to do + corrections on the S-AFC

Shadow

iTrader: (15)

Surprisingly it does. I've played with the fuel pressure from 18 psi all the way up to 65 psi, and the idle was not noticably affected. When I first put the 660's in, FP was at 45psi, idle was fine, but the car was hard to start sometimes, and mileage was pretty bad. So we kept taking it down 2 psi at a time over a few days until it got better and that was 24psi.