This is excellent advice for those of you that are racing your car or are going to change your oil every 2000 miles or so. If on the other hand you don't wish to change that often, avoid ALL racing oils. They really are designed for racing, NOT general street driving. The oil companies design them for conditions not encountered in normal street driving. The most important is that they are MUCH thicker than mobil 1, because race engines are started warm and brought right up to temp (unlike you car which usually gets driven before the oil reaches 100+ degrees). In the case of the average driver, you start the car, put it in gear (usually within 30 seconds) and drive off. That's ok, because your regular oil is thin enough to start coating parts as it is, racing oil isn't. I'm not positive, but in the case of DC using racing oil may void your warranty.