I just put in a summit hei distributor and set it up with the vacuum plugged and set the baseline to around 12. When I hooked the vacuum up to the full manifold port on my carb it went up to almost 40 degrees.
The idle ran great like that, but is this too much? Is the vacuum can supposed to put that much advance on it?

I also tried using the timed vacuum port and in that case at idle it didn't do much but if I cracked the throttle at all it would jump up to about the same point. Will I hurt anything by running this much vacuum advance if I use the manifold port?