Vacuum/Mechanical Advance Dilemma SB340

I can add more timing. I assume this will help idle. There will be a limit as I believe the compression is not low. The guy who built it put a big cam in it so he probably went min with 10:1 my guess. I sure wish I could upload a video so you guys could hear the idle.
I will do a dry compression test on all cylinders its going to be a while as I am still out of commission medically. So I I weave that into the plan. What information will the compression test give us with respect to tuning etc?

Ok now regarding the cam. I had an engine builder shop look at the engine as it was taking more than 52 degree of total timing. The guy said something was not right. He pulled the water cover off and as suspected there was an offset on the chain As can be seen here. Was this a problem? Is this how you advance an engine internally? By 10 degrees?

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Run the compression test and report back. That will give us a lot to go on. Keep in mind compression ratio has zip to do with cylinder pressure, which is what you will be measuring with the compression test. The two are related, but that's it.