HELP! 66 cuda idles fine, but not when in gear

Ported vs. Manifold Vacuum

If you can forgive the blasphemy of posting Chevy stuff, this is a good explanation of the ported vs. Manifold vacuum for timing that I was talking about. I also second what AJ said, I had to do the same with my distributor. after I got the timing set it was putting the canister right against my plenum.

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