Cujo, Sorry to be the bearer of bad news, but the offset key should be installed on the crankshaft gear, not the cam gear. You double the advance/retard by installing on the cam gear. This will kill any top end from your motor.
Removing the key from the cam gear can be touchy, it's easy to break the thrust plate.
I'm dubious about advancing cam timing. I've used the offset keys only to correct cams that are off-spec. If you buy the right cam in the first place, you shouldn't need to play with the timing.
Jack
www.inliners.org
