loss of power

[travisbconley]

I have a 79 2500 pickup with a 305 (holley 600, edelbrock performer intake, 400 trans) When I crank up and try to backup (after warming up) the engine sputters, and spits on the hill out of my garage. any ideas of what would cause this?

[Shrubby]

My guess is a flat cam if it has a lot of miles on it or bad fuel.
I'm told 305s are notorious for their cams going flat.
I'm putting a new one in my 305 Chevy pickup now and the old one was real worn.
It popped and back-fired and had no power whatsoever.
There are a myriad of things other than the above. Just look in any automotive repair manuel under trouble shooting and you'll see what I mean.
Good Luck!

[travisbconley]

the motor only has 500 miles on it. Rebuilt from the block up

[Mikado14]

Double check your timing.

[Shrubby]

Check the intake manifold for cracks.
You'll have to clean the dirt and crap from it first.
My pickup backfired and it also had a cracked intake around the carb.
Tighten your carb to make sure it isn't sucking air around the gasket.
Good luck.