Inliners International Forums General Discussion Engines Chevy 292, Rochester B carburetor main jet size?

The big 292 "B" carbs I have all have come with about a #72 Jet in them.

This carb is a lot like 1 primary barrel of a Holley 850 Carb, not the most responsive setup, huge venturi and throttle bore limited to 1.75" so I think the jet is kinda generous to give decent throttle response.

If you want to give up 5-7hp at the top end you can run a smaller car 1-bbl "BC" or "BV" carb, 1.25" venturi and about a #59 or so jet, a lot more responsive down low.