Flyman

I am pushing about 65 to 68 psi on my fuel pressure gauge on the end of my fuel rail. can this cause ANY problems?

Also would it effect my MPG?


Thanks
Steve

Black LS1 T/A

Do you know why it is that high? Did you get an aftermarket regulator?

2001CamaroGuy

iTrader: (6)

yse....its not a good thing to do on a stock (untuned for larger injectors/flow rate) car......

It will cause the injectors to flow more than they are supposed to (which won't hurt the injectors) and the computer will not know this. The computer will think they are still at stock flow and try to inject the stock amount. When this happens you will blow lots of fuel in, the car will go rich, the computer will try to adjust (might be able to), might hit its max adjustment level (+/- 25 = max out), and then after that won't be able to do anything. The motor will get far more fuel than it can burn which will not only cause poor MPG but can also wipe the oil off the cylinders and cause damage to the boors.

My guess is you have a blockage in the return line (either something in the line its self or the regulator is stuck closed).

Flyman

so an extra 10psi or so could cause that much havoc on my engine?

I have the fuel pressure regulator/filter from the c5 corvette, that has a .312 return line and a .375 main fuel line feed. pushing the fuel is a Walbro high pressuer inline fuel pump, and that's it.

Can I install an adjustable fuel pressuer regulator at the fuel rail without a return line from that? so it would be like this

Fuel tank
Walbro inline 255lpm
c5 reg/filter w/return line
then the adjustable regulator at the fuel rail

Would this solve my problem?

Thanks
Steve

Nasty N8

iTrader: (33)

You have a return line with the 97 C5 lines correct? There is an adjustable regulator available for those rails. With that much pressure it will be extremly rich if not tuned for it.

Nate

2001CamaroGuy

iTrader: (6)

what he said....

I swapped over from the F-body fuel rail (returnless) to the 97/98 Vette fuel rail (return line and regulator on the rail), used the EVP line (hard line) as my return line, removed the intank regulator (gutted it), and installed an adjustable regulator on the fuel rail. I think I got my regulator from LS1Speed but I didn't remember (been a long time). Be sure to remove the intake regulator or the rail one won't be able to do its job correctly (the min pressure will always be at or able the intake regulator's setting).

Flyman

No I Just have the fuel filter/regulator, just after the tank, my LS1 is a 2001

Shouldn't the computer adjust itself for just that extra 10psi? the reason I say that is that I am getting mixed info from several sources


I just want to know for sure, IS THIS A PROBLEM, SHOULD I BRING THE PRESSURE BACK DOWN TO THE RECCOMENDED 58PSI?

I will have to rebuild my fuel system

Thanks

Ryan K

iTrader: (11)

The computer will try to reduce the fuel flow to the motor but may hit the -25% LTRIM. If it does, then it will run rich all the time. If you tune the computer to think that it has larger injectors, then it will work fine. Keep in mind, most fuel injectors have a hard limit at about 85#. At that point you'll have to worry about the injectors "sticking" = BAD.

The computer has no way of actually telling what Fuel Pressure is, it can only go off of what the O2 sensors are telling it as far as being rich.

My recomendation is to either lower the fuel pressure -or- have the PCM tuned for the new increased fuel flow.

Ryan K.