My neighbor built an F7 this fall. He is an ex-ice drager, so I asked him what he has done to this sled. All he would say is it's got an F8 top end and mild porting. He was up racing some guys on a lake and there was one sled that he couldn't beat. That was an F8 on nitrous. There was F1000's and many other newer sleds up there. I talked to him today and he's got nitrous now and said on radar he hit 126. But he ran out of gear, so he changed gears and ran it again. 124 w/o nitrous. Just the motor makes about 165 hp and nitrous gives him another 30. It'd be nice to know what else he has done to it. Today he put on an SLP air horn while I was there.