[scottj]

The Centerforce problem with high rpm shifting is said to be caused by the weight system. Due to the weights, centrifugal loading continues to increase with rpm to the point of making shifting difficult.

I researched multi-disc racing clutches when building my car and all the techs at all the manufacturers said the same thing: "if you're going to use it on the street then call Red Roberts at McLeod and have him build a 10" street twin". It is supposed to be the best available for a street driven, high rpm shifting cars.
The twin disc design provides increased holding with less pessure and the 10" dia is the best compromise of low polar moment of inertia and the ability to launch without it being a switch. They also have an 8" but as the polar moment of inertia decreases, so does street manners.

Scott