I think he will be happy
With a 2.05 valve size. Using a 2.08 like I have only bumps you up to 315-318 cfm with a 195 cc intake runner. They become very touchy in that area and very dependent on short side size and shape.
I’m not sure where he will be shift at but my 408 went 5.98 which would be around a 9.30 shifting at 6700 rpm. I may step it up some next year just for a new best in some good weather but it’s just a bracket build so why beat on it. I keep hearing these stock blocks can’t take much.