I'm no expert when it comes to putting combinations together, so hopefully some of the other guys will jump in and help with that. My experience with the heads is this - stock x or j with a 2.02 will flow 210-220. Stock j with 1.88 will do 190-195. Stock Speedmaster will flow 250ish. Factory CNC'd Speedmaster (mine were a disaster) flowed 266cfm. The TF is 290-295 on my bench. In my opinion, the TF are as close to bolt on ready as you can buy. The Speedmasters need help from a good machine shop. I'd stay away from the factory CNC'd Speedmasters.