[kountzecobra]

If you are going to build a 427 Cleveland, you are going to have to use an aftermarket block or a 400 block because cleveland block doesn't have enough deck height. 393 is the max they build clevelands. I believe I would recommend an Edelbrock Torker and a 650 Holley DP. But try the 600 you have first on the Torker- it might surprise you. Performer is restrictive. Compression ratio is also a little low for 4v heads also. These Clevelands like compression! Your dyno numbers are really not too bad, I just think intake is limiting HP at higher rpm.