Polishing your stock throttlebody will not do crap. The reason why the dinan throttle body give 8hp is because it is a larger diameter. It has nothing to do with polishing. And before you ask, no you can not have it bored out to make the opening bigger. There is nothing to bore out. The walls on the throttle body are like a 1/8 of an inch. The dinan throttle body is an entirely new unit that is larger. Not a ported and poliched stock unit.