Thread: Figuring out which carb to get

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Check your manifold, I'll bet it's a spread bore because of the Rochester. The Holley is going to be a square bore and won't mate to the manifold with out an adapter (I don't recommend doing that). Look for a good aftermarket manifold that is a square bore such as a Performer from Edelbrock. Holley has a good one along with Wiend and others. Brake booster to manifold. PCV to base of carb. Simple enough. By the way the secondaries are fed off of the primary venturis. All internal so you don't have to plumb anything.

Vacuum secondaries are controlled by engine demand and Holleys have a spring kit that allows you to tailor when they start to come in. I'm a little conservative on CFM selection as I think a 700 is big enough for your application.
Manifold selection is a toss up in my opinion, but I've had good luck using an Offenhauser 360.

Denny, I agree with everything you posted, I'm just a little conservative on carbs. I've seen too many who think that if a 750 will work good an 800 will work better. Not true.