Carter used to produce a 400 CFM AFB specifically calibrated for the 283. Part numbers 9400s and 9410s. Best 4 barrel you can put on a 283; unfortunately no longer produced, so you have to look.

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