If you're just looking for around 60 on pump gas then a hardcore MX port ought to work with a good set of pipes, K&N filter/adapter or pods, +5 timing, and all the other goodies to go. I've heard of a 'shee or two coming from Herr Jugs making that kind of power with stock carbs, shaved head, and the aforementioned mods. I don't think it's too uncommon for that kind of setup but the others' opinions on the 4mil, larger porting, bigger carbs, etc. would make that number a lot easier.