I am thinking about putting a 440 kit in my 400ex, i know what is involved in putting the sleve, piston, rings etc....but i don't know if i will have to change my camshaft,valves, things like that.
I already have a stage 2 dynojet jet kit in it so will i need to rejet?

 

no you don't have to change your valves or cam, it is just a bigger sleeve and piston, I watched the guys at hollywood dirt do quite a few of them, they cut the old sleeve out on the boring bar, heat the cylinder up and drop in the new sleeve, and bore it for the new piston.

 

but why wouldent you want to put a cam in anyways, it wont make that much of a diffrence with just a piston and no cam or head work..