ls1transam84

iTrader: (1)

I have a 98 LS1 in my 84 TA and am having some fuel system problems. I have 90 psi at idol and 32 at full throttle. I believe this is because of the Vette filter/regulator I am running. Also, the more I run the car (hard) the worse it runs, after taking it out and beating on it I had to keep it around 2500 rmp just to back it in the shop. I believe this to be the pump heating up and not performing properly. Any input on this and the following questions would be much appreciated.
Is there an aftermarket fuel level gauge that will work with the 4th gen sending unit, my 91 gauge will not read the signal from the ECM, or is there a fix for my stock gauge?
Is there a pressure regulator in the fuel rails?
What is ideal pressure to the rails?
Any recommendations on fuel line size? (6An 8An ect...)
Thanks,

This car is a cam only (G5 X2) with headers an LS6 intake.

Rodder

iTrader: (2)

If you have 90psi at the fuel rail at idle, either
- the regulator is broken, or
- the return line is restricted, or
- the regulator is hooked up wrong

If you have 30psi at WOT, either
- the regulator is broken, or
- the filter is clogged, or
- a line is kinked, or
- the regulator is hooked up wrong, or
- the pump is too weak, or
- the power supply to the pump is inadequate, or

I'd fix the 90psi-at-idle problem first and see if it fixes the 30psi at WOT problem.

BTW, what brand is your filter/regulator? Is it a real AC/Delco, or a WIX?

bczee

iTrader: (12)

The Delco GF822 is set to a Max 57psi (give or take a few lbs). Replace that filter and put check the pressure at the fuel rail again.

ls1transam84

iTrader: (1)

I dont think it is a Delco, I cant remember, but I am running a Racetronix fuel pump kit
(98 f-body tank) that has a Warbo 255 pump. I am looking into removing the curent setup and replacing with a real regulator and filter so it can be adjusted. Any idea about a fuel gauge?

Rick Speed

iTrader: (55)

I'd use -8 pressure line to an aftermarket regulator and a -6 return with a high performance filter also

JAY ROD

iTrader: (1)

A 98 Ls1 would have a regulator on the rail on the motor.Do you have 2 regulators on your set up?I am having problems not blowing vette filter/regulators.Mine are bought from partsource.Where did you get yours?

G-Body

iTrader: (4)

Only the 97-98 vettes had a FPR on the rail. The 98 f-body fuel rails didn`t have a FPR, it was in the tank on those.

ls1transam84

iTrader: (1)

If there is not a reg. in the fuel rail (as said) then no just the vette unit, mine came from Auto Zone. Where is the best place to put the regulator by the tank or motor?

G-Body

iTrader: (4)

You can locate the FPR/filter anywhere. GM locates it back by the tank because it produces less evaporative emissions that way, but you could put it in the engine compartment too if you wanted.

ls1transam84

iTrader: (1)

Thanks I was told by Hawks to put it up front beacuse that allows the fuel to flow more keeping cooler fuel at the motor. Also that it worked better up there, but they just did some work for me that I am not happy with at all most of it was half way done but full price so whos to say they are right!

G-Body

iTrader: (4)

It will keep the fuel cooler if you put it at the front. That is why GM locates it at the back, if the fuel is warmed up more before it returns to the tank it increases evaporative emissions. So GM locates it toward the back to keep the returning fuel cooler.....of course this means that the engine gets warmer fuel.