fuel setup ?'s

[bisket]

i'm having a problem, i'm running the quarter in 14.9, trapping @ 92mph and i have a fully built 4g63 with a 16g turbo.

i'm still running the 450 injectors (don't have enough cash for new ones), with a walbro 255 pump, b&m fpr, b&m fuel pressure gauge and that's it as far as fuel is concerned.

so i've done everything that i know to get the car faster and now i'm just down to the conclusion that i'm runnin extremely rich, i'm runnning 17lbs of boost by the way, what i'm asking is, without purchasing an safc right now (cash issue once again , is there any way to tune the fuel so i'm not running so rich? could i just get a differn fpr or what? and advice is grealy appreciated, thanks.

 

[RallyxDave]

Do you know for sure that you're running rich or just guessing? You've got a FPR to control the flow from the Walbro pump and only running 450 injectors/17psi on a 16G, I'd think you're more likely to be running lean with that setup.

Hook up a datalogger and I bet you'll be able to find out what the problem really is.

 

[RS entities]

from what i've heard the B&M fpr is shit and can only raise the fuel pressure, not lower it.

thats just what i've heard from multiple sources

chad

 

[doug]

Or you could be getting knock, which would retard your timing and cause a significant loss in power. Like Dave said, log it to tell for sure what's happening.

 

[ninjanick]

Yeah that's right. The B&M can only increase fuel pressure and I've also heard the B&M Fuel Pressure guage is another restriction in the fuel line. Usually, with a 255 pump most people have to turn down their FP. I'd log it and see what that tells you.

 

[optik678]

TUNE! What methods are you using to tune? Are you using an AFC or what?

My turbo is smaller than yours and I went to the track recently and I did a run with my FPR unplugged by accident and I did a 13.8 and trapped at 99. This was at about 12psi on a GT25 (Pretty much a T28)