I think my return line is too small...
I think my return line is too small... Hey all,
I have just gotten to the point in my swap where I can routinely fire up my LS1/4L60E swap but I have noticed a weird problem with the fuel system. When I turn the fuel pump on - Walbro 255 into '99 Vette FPR it pins the gage at 100 psi on at the fuel rail until I turn it on. The gauge would then read 58psi rock solidly and hold there until I shut it down. After shutting it down, it would hold at 58 psi for many minutes and gradually trickle down. Now for some reason or another I try to fire her up and the gauge stays pinned at 100 psi and then the car starts backfiring and sputtering. When you initially "prime" the fuel pump you can hear it running back into the tank.
I am beginning to think maybe my return line is too small or something and pressure is building up??? I tried running it for a couple minutes but this surfaced and I think maybe that is where my problem is. Do I need a vented gas cap perhaps??? I welded a sump onto the '78 TA standard tanlk.
Any and all help is graciously appreciated! I am posting this in the "panic section" as well...
Thanks,
BanditDave
I have just gotten to the point in my swap where I can routinely fire up my LS1/4L60E swap but I have noticed a weird problem with the fuel system. When I turn the fuel pump on - Walbro 255 into '99 Vette FPR it pins the gage at 100 psi on at the fuel rail until I turn it on. The gauge would then read 58psi rock solidly and hold there until I shut it down. After shutting it down, it would hold at 58 psi for many minutes and gradually trickle down. Now for some reason or another I try to fire her up and the gauge stays pinned at 100 psi and then the car starts backfiring and sputtering. When you initially "prime" the fuel pump you can hear it running back into the tank.
I am beginning to think maybe my return line is too small or something and pressure is building up??? I tried running it for a couple minutes but this surfaced and I think maybe that is where my problem is. Do I need a vented gas cap perhaps??? I welded a sump onto the '78 TA standard tanlk.
Any and all help is graciously appreciated! I am posting this in the "panic section" as well...
Thanks,
BanditDave
