I just put a new Wiseco 11:1 piston in my Grizzly 660 and I think my jetting may be off. The power is no where near as smooth and linear as it was with the old stock piston. My current jetting is a Dynojet kit with the 150 main, needle on 4th notch, and pilot 2 1/2 turns out and a K&N filter with 93 octane fuel. My buddy says that a high compression piston requires less fuel and that I am probably running rich. Is he correct? I checked my plug and it is a reddish brown color. The porcelain insulator was also brown and there were some carbon deposits around the base ring of the plug. Do any of you guys have experience with high compression pistons and how to jet them? Any advice would be appreciated.