I"m sure this has been discussed many times already BUT can someone shed some light as to why I have an off idle stumble on my Holly 4000.

The 1956  -  312 engine has an automatic trans. Already have a 57 tach drive distributor in the engine and have done Teds 4000 mod to upgrade the teapots circuit to use vaccum advance.

Float levels seem to want to be high in this carb . When set at float level specs it hesitates horribly. No vaccum leaks. Timing is at 6 initial.  I did bump it a bit as far as 10 with no help in the stumble.

Both the vaccum and centrifical advances are working.

It goes from a dead stop with no stumble. Its only when I am at 30 MPH or so and give it some gas pedal that it stumbles.

Dont know what else to check or recheck.

Suggestions.

Oldmics