i bought an adjustable fuel pressure regulator and am not sure what to set it at.
it has the stock injectors and stock intake.
motor is a 383 w ported and polished stock heads . i will change it soon just need the cash but for now just wondering what to set it at
whats stock pressure?forgot to check

 

my motor in my 87 IROC is a 350 w/ headers and i have it set at 46 PSI. thats prob. more than it needs,but it runs damn good there so im leaving it there. i would say put urs somewhere close to that,maybe more if ur compression ratio is a little higher.

 

TPI using stock 22# Fuel Injectors the AFPR should be set about 44/45 PSI.

 

Mine's set at 52, I'm running rich when I hit the nitrous, I should turn it down some lol but 48 ish should be ok, take it to the track n see what happens, hook up an ECM scanner n look at your O2 sensor voltage.

 

I would set it at stock and ramp it up as needed. What does your chip tuner say? Mine had the pressure set at stock and varied the injector pulse width. It will not work well if you just up the pressure without changing something in the programming. It will probably work but it will not run at it's best.

 

It runs fine without changing programming, hook up a scanner n get ure BLM's n INT's to as close to 128 as u can, under WOT it automatically sets to 128 so dont test at WOT, test under accellaration, going up hill, going downhill and cruising. We did a dyno test a while ago with a throttle body airfoil and a fuel pressure regulator - the airfoil didnt gain anything until we up'd the fuel pressure some more - more air needs more fuel and the fuel tables can only have so much variation, so playing with a regulator is an effective way to richen up the mixture without having to go through the ECM fuel maps. Thats why Crane tell u to use an AFPR with their slightly larger camshafts, so you don't NEED to go reprogram the ECM, altho ECM programming is definately the most effective method, assuming you can get it right. If you have access to a dyno with an A/F readout in your area, it's well worth the money if you can make 4 or 5 pulls for not much money - you can see exactly where ure goin rich or lean and can adjust pressure accordingly.