You guys ever looked at how much total timing, with everything hooked up, you are running at "all in" cruising rpms( say around 3000)?

34 degrees on my 462

So when the vac adv drops out at WOT you're only getting 20 something adv?

You should be measuring total timing with the vac advance disconnected

I know what you're saying but I'm more curious about how high the advance gets with the vacuum canister hooked up and the rpms up to speed. In other words, I'm wondering how much adv the can should be adding and kind of curious how much is too much.

No vacuum advance here, no need for it. I lock it out on performance oriented engines. Vacuum advance may help With gas mileage on a stock type engine but other than that there's no need.

No vacuum advance here, set total timing at 35. Running a MSD distributor.

Just measured my timing on my 428. 28 deg total then 50 total with the vacuum advance hooked back up

Sounds like 50 is about average advance with engine up to speed and everything hooked up. I ended up cutting mine back down to about 44. 50 just seemed like too much.
Got something weird going on now. Since i changed to mani vac now the car idles pretty good but sometimes the engine will just start losing rpms and eventually just die altogether. Almost like its running out of gas. Maybe just need to add more fuel to the idle circuit. Carb tune on the to do list.