Budget is a non-definitive term. Post your price point restriction. My ProMaxx 171s with 2.02" intake valve are at 270cfm from .500-.600 after a little port cleanup and unshrouding in the chamber. Standard Speedmasters would probably react the same with similar work. I can't comment on the SM CNC version. The ProMaxx Shocker CNC will hit about 285cfm but have a bigger valve. Be assured that you will likely need geometry correction with any of the Edelbrock knockoffs which adds a not insignificant cost. The shim kit is around $250 and the shafts usually need to be slotted, which I don't think is included in that cost. The Trick Flow heads have that correction built in and if I were to do it again, I would have just got the TF and would have been ahead of the game in cost. Only thing that saved me is getting the PM 171's used for less than half of new cost.