I've had several Autolite 4100s and still have one 4100 out in the barn, but I haven't run a carb in a long time.
Best I can remember, the 1.08 4100 was a 470 CFM unit. The Hi Po 289s got a 480 CFM 4100, and the 1.12 version was a 600 CFM carburetor.
You might check with Pony Carburetors...