[Schurkey]

Originally Posted by GordonGeesey

My fault for not specifying this in the original post: My carb guy/tuner has the vacuum advance completely disconnected. He says that with the way he has the timing set, it isn't necessary.

You need a new "carb guy".

[steve25]

To be fair here, yes he does need vacuum advance but maybe not at idle.

[Tim Corcoran]

I fully agree with others statement about your mechanic. Vacuum advance is mandatory for a properly running street vehicle. In fact you can do serious engine damage by running it without a properly functioning vacuum advance especially if you have cast pistons. The Q-Jet is a great carburetor, one of the best ever if not the best ever made for a street driven vehicle, but they need to be tuned for your specific combination and after 40 or 50 years they need proper overhaul for them to operate correctly. Cliff Ruggles literally wrote the book on how build and modify a Q-Jet carburetor. Cliff no longer does carbs but there are a couple other guys that frequent this board that are equality qualified to make a Q-Jet operate correctly. There are many that claim to know carbs but few really do especially for a Q-Jet.