box is kind of a PITA... I bought one and went w/ an extreme air bonnet. You can push a good amount of boost thru a carb if it's prep'd right. I was only running 6 but have seen 12 and up. I had an 8psi pulley on but sold the car before I could give it a run. I'm sure it would have been fine. Just remember to boost reference your fuel pump and you'll be ok.