280z LS Swap Fuel issues - need advice
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Teching In
Joined: Oct 2019
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From: Sammamish, WA
280z LS Swap Fuel issues - need advice The setup:
1975 280z
LS6 with Cams and Springs, 400 wheel horse power
Stock tank which was for Fuel Injection from the factory
New Walbro GSL392BX 67 gph/255 lph
New Corvette filter/regulator
New AN6 lines
Before redoing the fuel lines over the winter the car would hesitate on hard cornering during autocross. It was fine on the street most of the time. I replaced the entire fuel delivery setup and moved the filter/regulator to the engine bay. It was back by the tank. The issue still happens.
Also the Walbro pump whistles very loudly at times. It's not constant, but is happening way to frequently. It sounds like a belt squealing. Very loud. I'm assuming this is cavitation from what I've read. This happened before I switched everything out also, but not as frequently or as long.
I did have a pre-filter before the pump and removed that to see if it helped, but it didn't.
I have read of other people using this same setup and not having issues. If that is actually the case, it leads me to think there is some sort of restriction on my fuel outlet (rust, gunk?). The tank is currently out and there is no way to see past the baffling to tell if the output line is messed up without cutting off the top of the tank.
I'm trying to come up with a solution, and could use some suggestions. These are the things I'm wondering about:
Is the Walbro pump sufficient to suck the fuel out of the tank? I've heard it is not the best at pulling, and is made to push. The output line in the tank has a vertical section so there is some gravity to fight.
Is there a way to determine if the output line is clogged without cutting the tank apart?
Is there a better pump that has more pulling capability and provides the necessary flow to the regulator?
Other options I have seen and been thinking about:
Holly Retrofit in-tank pump. Requires cutting the tank but should solve all issues and allows me to remove the external pump and filter.
Low pressure pump feeding the Walbro. Not a lot of room for this. I have one and am trying to figure out how to make this work.
Surge tank with feed pump. Even less room for this.
Any advice?
Thanks,
Scott
1975 280z
LS6 with Cams and Springs, 400 wheel horse power
Stock tank which was for Fuel Injection from the factory
New Walbro GSL392BX 67 gph/255 lph
New Corvette filter/regulator
New AN6 lines
Before redoing the fuel lines over the winter the car would hesitate on hard cornering during autocross. It was fine on the street most of the time. I replaced the entire fuel delivery setup and moved the filter/regulator to the engine bay. It was back by the tank. The issue still happens.
Also the Walbro pump whistles very loudly at times. It's not constant, but is happening way to frequently. It sounds like a belt squealing. Very loud. I'm assuming this is cavitation from what I've read. This happened before I switched everything out also, but not as frequently or as long.
I did have a pre-filter before the pump and removed that to see if it helped, but it didn't.
I have read of other people using this same setup and not having issues. If that is actually the case, it leads me to think there is some sort of restriction on my fuel outlet (rust, gunk?). The tank is currently out and there is no way to see past the baffling to tell if the output line is messed up without cutting off the top of the tank.
I'm trying to come up with a solution, and could use some suggestions. These are the things I'm wondering about:
Is the Walbro pump sufficient to suck the fuel out of the tank? I've heard it is not the best at pulling, and is made to push. The output line in the tank has a vertical section so there is some gravity to fight.
Is there a way to determine if the output line is clogged without cutting the tank apart?
Is there a better pump that has more pulling capability and provides the necessary flow to the regulator?
Other options I have seen and been thinking about:
Holly Retrofit in-tank pump. Requires cutting the tank but should solve all issues and allows me to remove the external pump and filter.
Low pressure pump feeding the Walbro. Not a lot of room for this. I have one and am trying to figure out how to make this work.
Surge tank with feed pump. Even less room for this.
Any advice?
Thanks,
Scott