Slight Miss at Part Throttle

[DanEC]

Are you running all mechanical advance or do you have a vacuum advance distributor? It sounds somewhat like an over-advanced condition I had with my BB Corvette motor with a vacuum advance distributor.

A bad plug wire is another possibility. Seems they show up more under light load and idle than any other time.

[Jeff Frigo]

Originally Posted by DanEC

Are you running all mechanical advance or do you have a vacuum advance distributor? It sounds somewhat like an over-advanced condition I had with my BB Corvette motor with a vacuum advance distributor.

A bad plug wire is another possibility. Seems they show up more under light load and idle than any other time.

No vacc. advance. All of the plug wire are from 120 to 130 ohm resistance.

[jhv48]

Sounds to me like a slight lean condition. Try opening the idle air screws up a quarter turn after first adjusting them for max vacuum at idle.