Bruce ( Shrinker )

Greg,
Post 67. With that big cam, it is going to need a LOT more than 17* for best/smoothest idle, more like double would be closer.
One way of doing this is to use an an adj vac adv unit connected to manifold vacuum.

This is a most misunderstood subject.

People often tune the carb idle before dialling in the timing at idle, when it should be the other way round.

From D. Vizard:
"The optimum idle advance is typically about 35-40* for a short cammed street engine & [ though not commonly realized ] as much as 50* for a street/strip engine."

And [ scroll down to post #6 ]:
www.hotrodders.com/forum/vacuum-advance-hooked-up-directly-manifold-bad-47495.html