[Johnny406]

I know that a split duration camshaft is the better choice for our Pontiacs, especially stock and mild performance street applications that are running a full exhaust/cat converters etc. No doubt the Pontiac engineers knew what they were doing and restricted dog leg exhaust motors like ours certainly benefit more from the split duration than other class of motors do.

My question is: For a aftermarket head open exhaust racecar, is that still the case?

For example, I'm about to start building a new 428 to replace my long in use 463. I will transfer over my 74cc 292cfm KRE heads and will be running around 11.0:1 compression with my Hooker Super Comp headers.

I have a 290B6 on the shelf (.540 lift .255/.266 @ .050 duration) but would that cam be any better or worse than say a Comp 306S solid cam that is a straight profile (.555 lift .260 @ .050 duration)?

Again, open headers with 18" 3" extensions for the crankcase exac.