How can i make my snowmobile faster?

I have an 02 Polaris Edge XC 800 with M10 suspension. its a god sled but it tops out at about 80 mph and puts out about 7.5 rpm. i think it should be able to go allot faster and be more powerful, but im not sure what to do about it. my friend has an 02 edge xc 600 and his blows mine away. I just feel that since its an 800 it should go allot faster than 80. what could i do?