Ok now I have my bifocals on so I can add a little more info. A TrickFlow is about maxed out from the factory as they used a small seat so you can’t go much bigger in valve size. An Edelbrock and Speedmaster type of head can take a 2.08 valve and be ported to the 320-330 cfm area so they can and do
Outflow TrickFlow heads. Even with a 2.055 valve and a competition type of valve job can flow over 310cfm. My set of Edelbrock heads can run 9.30@2850 pounds on my 408. (2.08 valve) Indy heads can go 330 plus
