340 Static Compression Numbers and Test Procedure

I think a vac advance could be made to work.
Maybe even with this distributor.
Vacuum/Mechanical Advance Dilemma SB340

The more we learn the less surprised I am that the actual driving experience is as described.
I think with this distributor, best would be to see if it will like a little more initial. Say 20* @ 1000 rpm, then back down the speed to 800. It might want a little more fuel from the idle mixture screws. Put it in gear and see if it rpm drops less than before.

Check the timing at 800 rpm or whatever lower rpm it should idle at with more timing. If its 20* at 1000, it very well may be less advanced at lower rpm.

PS. No vacuum advance. Just forget about it for now.