Ok reduced size of main system air bleed made carb richer and run better. I will be trying that myself. Thanks for posting your results. On the venturi screws are some stamped numbers, if still there, need good light and good mag glass to see. That can be use full info. Came in different sizes, pressed in steel bushings, some times rust away. Idle air bleed .059 .063 .067 common, idle economiser down channel restrictor .055 .059 .063 .067 .

Uh oh, my "6" and "8" theory has been disproven. So is it safe to say the venturi cluster with the smaller bleed holes is the six cylinder one?
No it is not, measured one carb .0472 for slant. Will check more later.

.0472 or 3/64 fits main air bleed on slant carb

venturi hole .0670 or number 51 close fit, slant carb

So on a stock motor, which venturi set would be theoretically "better" for a slant six? Ones with smaller holes or ones with larger holes?

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Casually looking for a Clifford hyperpak intake for cheap.

looked at couple more carbs, go with the larger ones .

While your at it try swapping venturi screws.

Hmmm. OK. I will do that.

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Casually looking for a Clifford hyperpak intake for cheap.