It may have been on a 4.3 Mercruiser, but Mercruiser didn't put it there. wink

Cannot read the number, so cannot tell exactly what it is; but that style is a minimum of 500 CFM.

Something else to consider: I know it says Carter, but that is an FM clone, not a real Carter AFB.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop