[Excaliber]

jimmymac, not sure what the question is...

I'ver hooked mine up with both intake vacuum and ported carb vacuum and not run it all. Currently I'm running intake vacuum, primarily to address the 'run on' condition as I like to set my idle speed around 1000 rpm, which is kinda high.

Bear in mind not ALL carb ports are the same. Some provide intake vacuum, others are ported above the butterflies. Easy to tell, the engine speeds up at idle, or not.

MSD can provide the theoritcal specs for the vacuum advance, something like 10 degrees advance at 15 inches of vacuum, etc. etc. I've found the specs actually can vary quit a bit in the real world. My advance unit starts to advance around 10 inches, all though, MSD says it is more like 15.