Sounds like you already figured out the most critical aspect of owning one of these cars. As stated, on the first screen of the scanmaster is the o2 and knock retard. When you romp on it, keep an eye on the knock retard (right side). You don't want to have any knock, but if you have a little, it's okay (2 or 3 degrees). Anything more than that, LIFT! You will get some false knock usually on the shift and sometimes on the launch. But you have to be careful. The scanmaster doesn't distinguish between real or false. If it doesn't feel right, get out of it.