I have a 350 chevy with holley carb,when i get the timming were it should be it has a little hesatation
when starting out,but if you hit the pedal hard it will back fire. But if i advance the timming a little it will run real good! But if you shut it off when warm it dose not want to start,like it has a dead battery,so i put the timming back were it was and it starts right back up!   PLEASE HELP  

i don't know if this will help i read about a similar problem they took off the electric choke wire.  

You should be knowing exactly what the amount of ignition lead is that is causing the engine difficulty when starting - this can determine if you simply have too much initial timing or if you have severe heat-soak in the starter.

If it is indeed too much initial timing the best fix would be to employ a vacuum advance canister, that is if you don't already have one.  

i had a simuliar incident with a chevy van i had, it wasnt a 350 w/ holley carb, ( it was a quadrajet, 305   )anyway, if i was to snap it at wot it would pop out the carb, so i thought timing, so i slightly advanced it and all is well, shut it off go to start... slow cranking.. i checked my tdc and it seemed correct but i was off a tooth, realigned it, and it fixed it. i had my vac. advance on the bottom right side of the Q-jet, but im not sure what pulls on the holley.

i know youve probably already done this but i guess i would share a similiar incident, good luck  

WELL I CHECKED THE TIMEING AND I DO HAVE A VACUUM CANISTER, BUT I AM NOT SURE IF IT IS ADJUSTABLE.
JUST TO LET YOU NOW MORE ABOUT THE MOTOR IT HAS A DOUBLE PUMPER, STOCK HEI,CAMEL HUMP HEADS THAT HAVE BEEN PORTED TO MATCH MANIFOLD AND HEADERS,AND A 480 LIFT CAM AND VICTOR JR MANIFOLD. I CANT REMEMBER THE DURATIONOF THE CAM,IT IS A CRANE CAM!

THANKS FOR ANY HELP


PS I PULLED A COUPLE OF PLUGS AND THEY WERE A BIT BLACK  

WHAT KIND OF TIMING DOES IT HAVE?  

IF I SET IT AT 8DEG BTDS IT STARTS GREAT BUT HESITATES,THEN WHEN I SET IT AT 12 DEG BTDS IT RUNS GREAT BUT IT IS HARD TO START IT  

what if you backed the initial off a little and went with softer springs in the distributor to bring in the mechanicl advance sooner to try to combat the hesitation?  

4° of timing is causing all of this? I highly doubt it...

I imagine your hesitation is coming from somewhere else, like how about an overly rich "double pumper" carb dumping into a single plane manifold that is overkill for a engine with less than .500" lift?  

i sorry to go off subject, i was had a quick question..if at 8 btdc, and softer springs, what would that make that @ 2000 rpms??