k heres the deal electric fuel pump holley 650 dp mallory 4309 regulator.. when i try bumping the fuel pressure up to anything over 4 psi the car barley runs and fuel pours out of the carb.. what the funk is goin on?

 

Fuel pressure affects the float setting last time I checked, with more pressure "sinking" the float and raising the float bowl level. I'd double check the float setting, since you say it doesn't do it at 4psi or below.

 

What does the manufacturer of the carb. recomend for a supply pressure? Also, you may need to clean the float needle and seat. A little trash in there will cause fuel to get by, and that would be amplified by increasing the pressure.

 

6-7 psi is far more than most carbs need. They need flow, not pressure. If the fuel system will deliver enough fuel at ½ psi to keep the fuel bowls full under all conditions, then that's all you need. There's no benefit to running high fuel pressure.

As an example: Boat motors, even when they're converted car motors, run at max HP (fuel flow) for hours on end with about 1½ psi. Same motor you have, same carb almost. High pressure helps overcome a restrictive needle valve; anything beyond what's necessary to deliver fuel at the rate the engine uses it, is excessive.

http://www.overtons.com/cgi-bin/over....cgi?spec+2C2B See anything there that looks familiar?

Back the fuel pressure off to 3-5 psi. Check the float setting in the carb. Make sure there's no dirt or anything on the needle & seat, no nicks either part, and that the seat is properly screwd in with a good gasket.

 

i set it at 3 psi and it seems to run fine.. starts easy and it doesnt starve for fuel at full throttle so should i just leave it there?

 

That's what I would do.