hello all. im putting my old 355 in my camaro so i can dirve it some for now. then the turbo motor is going in.

i want to use the stock tank and i know they make a 255 lph pump. wich is 67 gph.
the motor in my s10 wich weighs 3165 with me it went 11.02 all motor
on spray it went 9.93 at 134.98.

im going to detuen the motor with a smaller cam. arround .530 lift and less dur. cam should be good to 7000. and less heads proably double humps with bigger valves and springs. the s10 went 11.50s with 1.94 and 1.5 valve duble hmps with no port work and a tunnel ram.
my question is 67 gph of fuel still dosent seem like that much.? does anyone know how much power i can make with a 255lph pump or 67 gph.
thanks

 

In-tank EFI pumps are rated at about 42 PSI, I believe. If only asked to flow at a carb-friendly ~6 PSI they can flow considerably more.

 

do you think a 255lph pump could support my 350 at arround 450hp detuned and a 150 shot of spray? carb psi would be 7 lbs. and spray psi 6

 

Easily the 450 HP. On spray, can't say for sure.

I am doing this exact same upgrade on my 454 SS truck right now. It's got a heavy-breather 454 big block in it (carbureted) that might push up close to the 600 mark on motor alone. I intend to use the exact same pump you are considering and I have every belief it will keep up.

The stock TBI pump that's in it now ALMOST keeps up (noses-over about 1000-1500 RPMs shy of my intended redline). And that TBI pump is nowhere close to the volume that a 255 Walbro should be able to deliver at only 6 PSI.

 

i think as long as i detune the motor some ill be ok with a 255lph pump.
sweet. ill post what it does.