Food for thought. Years and years ago BSA was prepping some BA10s for Daytona. All of a sudden the guys found another 3 horsepower. Where did THAT come from? Well it seems that an apprentice had installed a slightly smaller (I don't remember the details anymore) Amal. There was a lot back and forth head scratching, but when they reinstalled the bigger carb the 3HP was gone. The only reason they could come up with was that the slight step between the head and the carb caused a slightly better atmoization (word?) of the air fuel mixture, Personally I've always been fond of porting and polishing, but then sometimes I wonder---
