02TransAm/Batmobile

iTrader: (32)

in jan's hot rod issue, they replaced the pressure regulator with an adjustable regulator and and adjusted it from 42 psi's to 47 psi's and for the last set of mods they jumped to 52 psi's, . . . . . would this be a simple bolt on? would i have to change the fuel injectors? and would it be worth the 135 bux?

thanx

2xLS1

iTrader: (25)

Are you sure they weren't doing this on a LT1? All LS1s run 58 psi fuel pressure stock from the factory.

02TransAm/Batmobile

iTrader: (32)

yea, its jan 2006 "ls1 cookbook. 5 steps to 530 horsepower" "provisions were made to adjust fuel pressure by replacing the '99 style returnless fuel system with an Aeromotive adjustable regulator installed on a conventional return-style fuel system. The stock 42-psi factory LS1 fuel pressure setting proved adequate for the Stage 1 and Stage 2 combinations."

Plum Crazy Rob

iTrader: (3)

Apparently Freiburger forgot to read the factory manual on the 4-bar (58.8 PSI ) fuel pressure stock

Unless you have some kind of special situation, don't waste your time on
the AFPR...

PREDATOR-Z

While the info in the mag was innacurate, what is accurate is that a FPR at the rail is a nice addition to any setup.
When you're going WOT, your pressure drops as much as 4>5 points on the standard setup.
Going FPR@R will allow you to dial in your pressure at WOT to stay 58 psi.

Plum Crazy Rob

iTrader: (3)

How is the FPR going to raise the pressure above what was already being
supplied by the pump at the same rate of flow, Predator

At the FPR inlet, you may now show a steady 58 PSI on your gauge, but if your real problem was net fuel delivery (volume/pressure combined)I think that would still show on a gauge at the FPR outlet (and as delivered to the injectors)

I could be wrong though

On the other hand, if you're implying to put on the FPR and crank the fuel
pressure up to 63 PSI so that it only falls to 58 at WOT, that is different

PREDATOR-Z

Bingo!!!
I have a racetronix 255 PnP, harness and FPR@R.
A regulator is what it is, it regulates (stock system has one). The only other issue that can limit pressure increase is size of line and size of rail.
A regulator at the rail is adjustable, so as long as fuel delivery is ample, I put it at 62 psi and at wot it is regulated to maintain 58.
That is one of the reason poeple tend to oversize injectors, simply because their fuel pressure drops and doesn't allow the injectors to sustain their flow rate.
I run 30 SVO for 550+ rwhp on juice.

Got Me SOM

iTrader: (2)

i take it you don't have the stock returnless system anymore. I desperately need a regulator.
my racetronix is 60 at idle and drops to about 53 under w.o.t. i could only imagine if I had put the bigger injectors in there it would drop worse..

PREDATOR-Z

Correct about the return system but bigger injectors would not see more drop with the same demand.

Plum Crazy Rob

iTrader: (3)

Great, glad you didn't take my reply the wrong way
Taxing the limits of the stock fuel system (as you and I are) was what I meant when I say "special situation" might benefit from an AFPR.

Got Me SOM

iTrader: (2)

gotcha I thought for some reason since i'm stepping up to 50 lber's they would be delivering more volume so my pump would have to work harder to keep up.

Guess I gotta put a return line in my car. How difficult was it to do? did you do rails as well?

I was quoted an astounding 1500 bucks for lines, rails, regulator mounted on the rail, etc.
i was like fawk that. I think that might have included a BAP, but honestly at my power level I shouldn't need a BAP, least I don't think..

when I had my stock pump with the trex, the fuel pressure stayed rock solid at 60 even at wot.