They're called cam ground. When cold they're elliptical. They are designed so when they heat up they become round. So in order for them to work, they have to have the proper clearance, which is a good bit more than a cast or a hyper, hence the extra noise. A lot of machinists give them some extra clearance as a cushion and they make even more noise. As long as they're forged, it won't hurt a thing. I THINK that's what you have going on. Just cool out on something else for a while. When you're able to actually drive it for a while, then we'll know for sure.