Well, compared to my stock 2.02 J-heads they aren't far behind. My build is going to to be street and road course oriented so I think I'll have to go about it differently from someone that is focused on quarter mile games and that 30 cfm may not manifest itself as much. The biggest flowing head my not be in my best interest, though it should ultimately make more peak power. I still need to decide if I stay with the stock crank or go with a 4" arm.