Vacuum Advance Question

Hi all,
I'm having a heck of a time getting my vac. advance to work properly.
LA 360, Comp 20-418-3, performer intake, 1406, stock distributor, FBO ECU & Chrome ECU both act the same.
20* initial-34* total.
When the canister is plugged into either port, the thing won't run.
Manifold vacuum : dies immediately
Ported vacuum : coughs and farts, then dies.
The question...how much advance does everyone need typically from the canister? I've got 3 different ones to play with. One is blank, one is marked 8.5,the last is marked 11.0
This is obviously a street car...lol