So I'm not new to mustangs or cars in general but this is my first motor build. I plan on putting around 500 horses to the ground. I was looking into balancing my bottom end because I got killer deals on a rotating assembly. I am definitely going to get everything checked for straightness and stress cracks because they are used, and I am definitely getting my rods and pistons balanced even though they are already assembled and probably OK. My question is, how important is it to get my crank balanced to my dampener and flywheel? I've heard my motor is internally balanced. The reason I ask is because my machine shop sends parts out to another company to get it balanced and they want about $400 just to do the crank. Its an 03 cobra block and a 98 cobra crank if it matters.