moper
Well-Known Member
One of the first things I always do, is discard the factory 5/16 fuel line from the tank, all the way to the engine. I think it is the biggest overlooked restriction with a lot of projects.
I've run the factory 5/16 line on 440s running a mechanical pump and high 11.60s at 115. It's not nearly as much of a problem as many think until you really need to move some fuel. What is important is steady fuel pressure, fuel level in the tank, and if a mechanical pump the ability of the pump arm to follow the rod or eccentric at higher rpm. With one power valve and four jets of around .088" you have enough flow as long as the pressure is 8psi and the pickup never gets uncovered. The problem is most mechanical stock-type pumps only push about 5psi at best and a lot of non-racers run 1/4 tank or less. A friend with a 383 RR was disappointed after I did some carb and tuning work for him at the track and the car didn't pick up much. So I got in it, turned the key, and he had under 1/4 tank "because fuel's heavy". I put 1/2 tank in it and the car dropped 8 tenths.