GregGold

iTrader: (1)

My ls1 originally had a return line on the fuel rail, but it was replaced with one that does not have a return line. Do I need a special pump with an internal regulator or do I need to go back with a fuel rail with a return line?

Why do some rails have return lines while other do not?

Thanks.

crainholio

iTrader: (2)

You can either add an external fuel pressure regulator and plumb its return to your chassis line, or just swap your old rail back on.

It was a design change, most likely cost cutting. Hard to say which is better, so just go with the easier solution for you.

SUPERBOOST

iTrader: (11)

I think the easiest and probably the cheapest solution is get you a 2000 corvette fuel filter/regulator and mount it close to the tank with a short return line to the tank.Cost about 40 bucks.

rockytopper

The 99 vet filter regulator works well with an internal or external pump.

slow

iTrader: (7)

part of the reason for the change was for the new EVAP emissions standard in 1999, so they went to the returnless style in 1998 on the f-cars, and in 98/99 on the vette.


Ryan

bczee

iTrader: (12)

+1 on the Emissions reasons.

You can go either way.. what car/truck are you swapping the LS1 into ?.... if the car/truck only has one feed line and no return, then use a Vette FPR in the rear near the tank and just use the one feed line.

If you have a return line on the Car/Truck and want to use it, then swap back to the fuel rail with the return line on it and connect up both the feed and return lines. You may want to look into the regualtor of using a OEM setup or a aftermarket one.

TomH

iTrader: (1)

The filter/regulator is the easiest (cheapest) solution. If you already have return lines plumbed from the rail, you can mount the filter anywhere along the existing fuel/return line between the tank and the rail that's convenient and start (connect) the return line there. Done!

Good luck.

GregGold

iTrader: (1)

I appreciate the responses.

My project car is a 94 Infiniti J30t, which has a return line.

The original fuel rail was damaged and unusable.

Does the return line style fuel rail have a regulator built into it?

Is there a procedure/issue bleeding the air out of the non-return style rail? It seems, that may be an issue if the the car ever ran out of fuel.

My next challenge will be figuring whether the factory fuel pump is capable of 58 psi. From what I understand this car has a computer controlled, variable pressure pump. Supposedly, at normal operation, it produces normal pressure and at WOT, the pressure goes up. Not sure of the particulars. I am going to try to find the pump feed wire and see if 12volts will supply enough pressure. Would be nice to know what that pump is rated for/capable of.

Is there any performance gain in attaining more than 58 psi?

rockytopper

The fuel rail with out return as a bleed port on the fwd drivers side. Like a tire valve stem.

Rodder

iTrader: (2)

I run returnless rails and I didn't bleed the fuel system. On my first startup, it took about 10 seconds of cranking to get fuel to the injectors, and another 10 seconds for the idle to smooth out.