another total timing question

The vacuum advance does not work "like that". Turning the adjustment screw does not change the amount of timing the vacuum can pulls in. It changes WHEN it pulls it in.

Probably be better if you actually READ UP and learned what you are doing instead of just plowing ahead without understanding.

They make these things called books. You can access them any time you want and not have to wait for someone on a forum who may or may not be correct to answer your question.