I am going to be running mod 2wd from now on, done with "stock". With all of the new technology in speedos in regard to timing advance and different software available all the time, there is really no such thing as stock anymore. I am thinking about running a 7.5 in my buggy and truck, but a friend of mine doesn't think the diff in the GV2 will hold up to that much power. I have ceramic balls and planning on a B Fast job. Has anyone ever had problems with the diff while running a mod motor? I have never ran anything hotter than a 10.5 in it. Thanks guys.