[Formulajones]

Originally Posted by i82much

I have the stock MSD Ready to Run canister hooked to manifold vacuum. It pulls 15" or so at the current idle speed and the idle speed drops noticeably if you disconnect it. The engine does not ping at light throttle so I can't see a strong reason to limit the vacuum advance.

That'll probably work just fine. I've found the MSD distributors usually run a vacuum can very similar to the old B30 can. That works just fine without limiting anything.


The problem these days is finding those cans. So I end up taking an adjustable can, start the limit at about 6 inches of vacuum, and then weld the shaft to limit the rod travel to about 12 degrees of advance at the crank. An engine not as sensitive to pump gas you can add another 2 or 3 degrees.

Then it works just like a B30 can.