Easy Advice and Recommendations

Are you tuning it by the book numbers? If you don't have emissions, which you appear not removing all that junk, throw the book numbers in the garbage. They were established to meet smog standards back then, not where the engine ran best.

I'd set the initial timing at 10-14 and get the total in the 34-36 area at 2500-3000 and see how it runs. Takes some work, but the benefits of the engine running more efficiently at idle are huge all the way up the rpm range..