Big cam, inconsistent vacuum, the very reason not to run full vacuum advance at idle.
Initial timing is crucial when tuning a carburetor during idle and transition.
Again, what happens when you mash the pedal, all the vacuum advance, say 10 degs goes a away.
All I can say is, Vixen's engine likes ported best and I've tried manifold, ported and leaving it plugged. The cam is [email protected] on a 108 so that qualifies as a "big cam" for a slant 6. It only has 6hg at idle.
