They come pre programed with 4 curves, all a lot better then the std cr curve. We built s new curves with mine. We gained 4hp with a much better curve, and was able to keep the motor cool with it with thw timing advance. I think when we put it on we got 2 hp right away. My motor just needed more timing. It is a very nice piece, not cheezedick piece like a dyna! And yes thwy are still in the 400 range