The first BIG mistake I see is the rubber O ring on the groove in the housing. That groove needs to be empty, as the O ring will restrict the movement of the vacuum advance. It's only there to keep crankcase oil from migrating up the housing due to splash and leaking to the outside. The housing is also aluminum- - - -bad juju, as it will wear quickly from the constant motion of the housing responding to every change in ported vacuum to adjust the timing. There's a good reason the OEM distributor housing was cast iron. I'm a little bit crippled, but I think I could outrun anyone who wanted to GIVE me that distributor!

Edit: To make that one work with some degree of longevity, I'd turn the housing diameter down some, and press a brass sleeve bushing over it, instead of letting the aluminum ride directly against the block.
Jerry

Last edited by Phak1; 07/20/2026 11:41 AM. Reason: Typo
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