Performance timing

Go find my post where I gave step by step instructions by bumping the timing up 2* at the time at idle in PARK and do it. You will begin to understand what's going on if you will just DO IT. You will see the effect of timing on an engine if you just DO IT. You can always put it back, and you will need to because you have no way to limit total timing yet. But in order to get it done, you have to DO IT.

Now, the reason your distributor is pulling so much timing in at idle is because you have the advance can hooked to the wrong port. You need to find the port that has no vacuum on it at idle and has vacuum on it when the throttle is opened. THAT is the correct port. It's called ported vacuum. BUT, as of NOW, you don't even need to worry about the vacuum can YET, until you figure out how to adjust timing and what effect it has on your engine. You're not going to hurt it. But in order for you to learn, you have to DO IT.