is there any increace of psi ? is it safe ? any comments

 

i got a AFPR from a buddy and he had lost the disc that came in it... so we just put a quarter in it when we put it on my car... may be a little thicker than the stock plate in yours... so possibly could increase PSI

 

Yes - it bumps PSI a bit... but it is not logical! There is no mediation if you are attempting to tune the car. You have to just "hope" that it will work. I would suggest running the car at the track, back to back w/ and w/o the quarter in the FPR.

 

Is 52psi killing performance, because i did not notice any difference when i raised it? its home made and 52psi is the lowest i can set it....

 

So if you took time to test & kept working with it, you could keep filing the quarter down til you came to the right pressure and it'd work fine?

 

Sure... but what a damned pain in the *** that would be.

I would buy an AFPR - that way you can tune whenever you want. A small note on this: Adjusting fuel pressure to compensate for more power is at best a band aid... the right way to do this is to pair it up with a custom prom.

 

Ditto that

...or modify the stock FPR to be adjustable.

 

My (sarcastic) point was that you'd spend more on gaskets and labor doing all that testing than just buying (or making) the AFPR to begin with.

 

I have a quarter in my FPR and it raised the pressure by 3 psi. The only think is that when you do that you can't lower the FP unless you remove the coin.

It is a good mod for 25 cents.

 

It's a perfect mod for a stock/bolt on car, ups it just a couple psi, about where you'd be setting it with an AFPR for about $49.75 cheaper...

I did it on my old 86 IROC several years ago, certainly no ill effects. Might be hardpressed trying to tell the difference on the seat of the pants dyno though. That in conjuction with ported plenum should be noticeable though (was in mine, did those two at the same time).

Unless I'm mistaken somebody had tested it at the track, was worth like a tenth for 25 lousy cents, I call that more than worth it...

 

The only way this would be a ok idea is if you burned
your own chips or had a DFI
You are assuming everybodys injectors, fuel pump, battery
power,and FPR spring is the same. How would you adjust the fuel pressure
at the track or dyno?? Everytime you change one thing you
need to check everything else in the loop. You can make or
buy a AFPR for $60.00 tops. I think for the guy that can't burn
his own chip or adjust his computer this is a must have item,
and should be first on the mod list. (with a gauge)

just my $.25

 

i did it on my car today and rasied it 12 psi to 52 and was worth 25 cent instead of buying a afpr casue why whould u go more than 52 with little mods

 

Why bother when you can modify the stock FPR for about a buck.

A fine pitch bolt, matching nut and a electrical box knock out will convert the stocker into a AFPR. About the only hassle is getting the nut brazed to the top. (I just mig'ed mine).

BW

 

Why bother increasing the FP. The stock programming on these car are overly rich at WOT anyway...........

 

Good point Slow89.

Unless you start getting into the prom, increasing FP will actually slow you down at the top end.

The only time you will feel a difference is if the car has been running lean due to heavy mods but if it is a stock car don't bother.

PS. Since i increased my FP I went through 2 fuel pumps in 2 years.

 

EXACTLY. People are constantly raising their fuel pressure on basically stock engines when they don't even know IF they need more fuel. Worst, raising your fuel pressure to 52 psi on a stock fuel pump is sure to result in a pre-mature death to the fuel pump.

I recognize many on the guys that have been responding also on the DIY Prom Board. Most who have tried tuning a basically stock engine have found that they need LESS fuel, not more.

There is a debate whether higher fuel pressure and better atomization really do anything over lower fuel pressure. I personally prefer higher fuel pressure, but not beyond 46 psi, especially on a stock fuel pump. But I also acknowledge the problems pointed out by people that advocate running a lower fuel pressure.

"The excessive strain high fuel pressure puts on fuel pumps doesn't seem to be worth the trouble it causes. Especially when you can adjust the fuel properly within the eprom."

 

What fuel pressure were you running and have you lowered it?

 

i have ported plenum, siamesed runners and headers so i figured it'd be ok for me to raise the pressure to 50. i know best results come from doing changes to the prom, but that's still somethin i have to learn more about.