Another Carb Size Question

First, you should probably post some info on your engine. 373 ci is good info, but what intake, cam, compression and exhaust manifolds/headers? That's info that's really needed to pick a carb.

Just based on the displacement though I would say that a 750 cfm carb is going to be closer to the right ballpark than a 650. Mopar Muscle magazine did a dyno article on a 340 they rebuilt to stock specs, stock cam, pistons, the whole works, including an original Carter AVS carb (~600 cfm). They ended up with 281 hp at 5200 rpm and 328 ft/lbs at 3900 with all the stock gear. They also found that they were running lean at the top end.

For their second set of pulls they bolted on a bone stock 800 cfm Edelbrock AFB carb, straight out of the box. They ended up with 316.9 hp at 5200 and 351.3 ft/lbs at 4000 rpm. Thats a 35 hp increase!

Now, thats a bone stock 340. I'm guessing that your 373 is a far cry from bone stock, so while I'm not sure what calculators you're using, I'd go with at least a 750cfm carb...