318 with Carter 2-bbl fuel leak through throttle shaft after hot engine shut-down

I've only really had the car running with this carb since July this year after a couple years of r&r (and 20 years of storage before that). I've checked the plugs after long highway runs and they are super white. I've disconnected the vac advance to stop a tick I hear at highway cruise. I run 10 or 12 btdc and even with 93 octane I still get ping while hard acceleration from a stop. I think I measured the carb throttle bore size and it matched the old actual carter bbd this engine had back in 1985 - 1999.

This carb was billed as being for 318 and slant-6 but I don't really know if back in the day (1977 ?) there was such a carb for both the slant and the 318. Or maybe same carb just jetted differently.

But all that aside, I don't think it should be leaking through the throttle shaft (seems only the driver side) during hot-soak engine shut-down / cool off. ?


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The bore size is likely the same slant 6 to 318. It's the venturi size and jetting that's different. That's why your plugs are super white and possible why it's got spark knock. Too lean. You need the right carburetor.