11-27-2006, 11:40 AM
If you want to get picky about the oil change interval, you can have the oil analyzed every 3k or so (blackstone labs, napa, few others) and they can tell you how much longer the oil is good for. IMHO, changing the filter is more important than the oil if you are using a good synthetic - oils are pretty damn good these days and will hold up just fine at 300 deg in track conditions.