[HWYSTR455]

I say vacuum advance isn't necessary? Not sure if that was to me, but I've always said full manifold vacuum is the way to go.

Yes, metal to metal, and no, it won't leak. It's a machined surface torqued at 120, there's no seepage unless it's not machined right.

Ask Butler then if BOP, who makes the seal, isn't trusted.

https://www.bopengineering.com/seal_instructions.pdf

Just going to have to disagree on this one, please don't take it personally.

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