This was way more than I expected. While this was on my C6, it certainly applies to the C5. I have a 427 C5R with a very small (224) cam, Kooks headers, Stage III 6 liter heads and that's about it. The best it's made is 390 RWHP and 418 RWT. I can't tune it and the torque management seems to be killing it.
All I did was swap the heads for a set of my custom ported 240 CC AFR heads and add a FAST manifold, that's it. ( I had to cut the back of the manifold off and reshape it with epoxy to get it on!)
I drove it around the block and was shocked. I went right back and strapped it on the dyno. I ran 3 runs back to back and all 3 were within 1 HP and 1# of torque. It made 462 RWHP and 473 RWT. This is still with the torque management in play.
I'm in the middle of a project using these heads with 12:1 compression and a 256-264 -112 cam!
That should really show the potential of these heads. The flow #s are very impressive but I think a lot has to do with the chamber shape. I hope to see some impressive results shortly.
Linear Mode
