My motor just got fresh new heads, and I'm loving the way my engine runs now. The only thing is that when the engine is cold, I can give it just a small amount of throttle while its in park and it runs rough (just off idle). While driving that same just off idle throttle position is even worse, almost making the motor cut out and sometimes causing a backfire which I think is through the carb. Giving it extremely light throttle or half throttle+ is fine. Once it warms up the problem is barely there, almost unnoticeable. I'm thinking I need to double check my valve adjustment, but I'm not sure if that's it.
'83 c10
'79 350 with summit cast iron heads (close to stock compression)
tried 8 and 12 btc. initial timing (no big change, but 8 seemed better)
Edelbrock 1406 (practically new)
stockish cam (afaik)
stock hei (non-esc)
choke adjusted fairly well--tried both extremes with no change
**just tonight noticed what seemed to be a small vacuum leak from vacuum advance unit on distributor, but don't know if that's significant
I have verified visually that all valves are moving about the same, I don't think its a worn cam.
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