That's what I suspected. I think you have valvetrain instability that is limiting your rpm. I also think the cam is too big for that compression ratio. You need cylinder pressure and the only way to get it is with more compression or a smaller cam. Advancing the cam will help too, but it will take away from the top end. A cam about 15-20 degrees smaller and correct the valvetrain issues, and it will be a totally different animal.

Mike Beachel

I didn't write the rules of math nor create the laws of physics, I am just bound by them.