I was just looking for an alternative to replacing my stock cam. Basically, all I am aiming to do is increase the lift of the valves and the only thing I could think of is shimming the valves (I'm not all that interested in increasing the duration all that much, especially as much as the HotCam does). After further research I discovered that maybe only valve trains that don't incorporate a rocker arms can utilize valve shims. I have thought about megacycle doctoring up my cam and rockers/arms. I've been to their website but could not find any info or specs for the 650L. Probably need to contact them by phone. I know there's at least one guy on here that uses a megacycle cam, can't think of his name at the moment. What I don't know is if he sent his cam to megacycle and have them doctor it up or....??? Any help would be appreciated.