I would get with Tim (if i was you) in regaurds to try and find out whats up with that.
Vacum to the dist is normaly ported Not straigh off the manifold
straight maifold vacum will normaly Pull the advacne full And it can over time put a hole in the advance diafram. So my guess is if it is doing so and your diesling issue is now gone.I would say you need a little more timing to start with.
On some vacum units you could put your finger under it and feel it move in and Out as vacum pulls on it. Un plug your vacum try and feel for the rod going into the dist. See if it pulls it at idle. If so You will need a ported vacum source Which should only pull as you come off idle.Another words while giving it the
gas.
God doesn't like ugly.
