[aigel]

What will you get above 6500rpm? It won't make you faster, unless you have more umph up there too whis isn't the case on a stock engine. It's asking for trouble in my eyes. At that high an rpm, the piston chases the exhaust valves when it is closing. I'd be afraid that the piston wins the race. BAM!

Build the engine with the right tolerances, ARP rod bolts, aftermarket rods, stronger (quicker return) valve springs and cam / intake / exhaust that produce the high rpm power and you are all set.

Don't rev the snot out of a stock engine. It doesn't make sense, unless you are an engine builder in need of business. My $.02

Cheers, George