Thanks for the reply Ato. I understand the vac advance. The dist. just has play in it. Running or not I can turn it 1/8 inch or so in either direction, like its just worn. I can't understand why it would be fine the first couple of downshifts after timing and then backfire again. Seems like a timing issue huh?
I could reinstall the manifold gaskest again, maybe its a small exhaust leak.
I keeping at it.
