Learn about the benefits of manifold vac adv. It is a LOT more than economy.
You may have to type in the full title. Scroll down to post #6:
www.hotrodders.com/forum/vacuum-advance-hooked-up-directly-manifold-bad-47495.html
And this from D.Vizard who has forgotten more than many will ever know.....
" At idle & low speed operation, the amount of advance reqd to most effectively utilize the air & fuel entering the engine can be
as much as 50 to 55 degrees. This is handled by the vacuum advance: a function many hot rodders believe is not needed because their favourite drag racer does not use it.
NOW IS THE TIME TO LISTEN UP & LISTEN UP GOOD. A FUNCTIONAL VAC ADV IS IS THE SINGLE MOST EFFECTIVE CAMSHAFT TAMER YOU CAN GET.
By taking the time to hook up the vac adv to a
manifold vac source you can get a big cam to idle as it were 20* & less than it really is. Conversely, if you sre loking for a decent idle, the use of vac adv will allow you to use a cam of,
at the very least, 5* more duration/overlap than would otherwise be the case."