Does anyone know or have an opinion on if there is a horsepower difference between using a small bell vs a big bell carb? Thanks in advance.

All I can tell you is I had a small bell carb on my 270 and something got caught in the needle. Because I was trying to make a Consi I installed a spare bill bell carb that was on an engine I had just bought. My lap times didn't change as per the transponder.

You decide.

We have never seen a difference other then the filters cost twice as much.

This year we ran both Carbs. There really didn't seem to be a big difference for us.