Thanks for all of the previous help, been busy working on my '76 two-door V8 swap and its coming together nicely.

But...

I have a mechanical Holley 80gph pump, Fram clear fuel filter and a Holley in-line fuel pressure gauge. When the engine is first started (cold) the fuel pressure reads 7psi (the spec is between 5 and 7.5 so this is good). In addition, the clear fuel filter is chock-full-o-fuel.

But after taking it around the block, popping the hood and looking at the fuel pressure gauge, it reads 1.5psi and the clear fuel filter is almost empty (maybe a tablespoon of fuel in it).

Needless to say, it will idle fine like this but spits and pops if any load is placed on the engine (not enough fuel, I'm sure!).

Any ideas why the pump isn't pumping well when the engine is hot?

Remember that this is an inline-6 (250) to a 302 V8 swap with Heddman Headers. A friend suggested that the fuel line was getting boiled by the headers and causing the pump to suck air instead of fuel. I am inclined to believe this because the fuel line from the body on the inline six engine is just aft of the drivers's shock tower, whereas on the '73 V8 donor car, the fuel line rides the frame rail and exits in FRONT of the driver's shock tower (keeping the line cooler?).

I would appreciate it if anyone else has any input on this. It's driving me batty!