i have a 8ba flatty with a stock dist with a petronics ignitor i want to use a pair of speedway 97 carbs they have no vacum porys for the spark adv can i use manifold vacum
The 8ba distributor is a vacuum-only unit that requires the stock carb with its special vacuum port, manifold vacuum will not make it work right. If you swap in a chev distributor, or an aftermarket one, then manifold vacuum will work.
I'd do a little homework before dishing out the bucks for those speedway carbs. AND, I'd throw that loadamatic distributor away and go with mechanical advance. I get my carbs from Uncle Max and Distributors from Bubba. That way if they don't work I have somebody to piss and moan to..............