RonCT

Well, I would run say 10 track days a year and each day would end up being about 250 miles depending. So 2500 plus another 2500 to / from track and general street miles = about 5000 a year total. Northeast is tough - snow probably from early November through Early April...

David993S

There's an old saying, especially as it relates to the "Showroom Stock" categories in racing (and probably for cars used for track days too) that one track mile is the equivalent of about 100 street miles. I always found it to be true, more or less, from a maintenance standpoint. Certainly track miles subject a car to much more wear & tear than normal street driving, assuming you're actually pushing it on the track.

RonCT

After many years and with confirmation via oil analysis my process worked out fine. I can't buy onto the equation that 1 track mile = 100 street miles. Stretching legs at the track is probably better for a car than stop & go street miles or short trips. As to pushing it, I'd say 1:01 at Lime Rock in a stock 997 C2S is moving along

DaveHak

My 2 cents, Oil changes should be based more on milage then time. Specially true with synthetic oil, since they do not break down like conventional oil does.

David993S

I agree that certain aspects of track driving may be easier on a car than street driving with lots of short stop & go trips. Consider this: let's say you turn one fast lap at Mid-Ohio on the club course (2.4 miles) with your stock 993. By stock I mean stock brake pads, street tires, suspension, etc. I can absolutely guarantee the wear you would put on your brakes, tires, suspension, gearbox, and other components are far greater than 240 miles of "normal" street driving. However, that same lap probably would not put the same 1:100 equilaventit on your clutch disc, for example, assuming you're smooth and not abusing the equipment. It's probably the same for oil and I would believe the data you've seen from your oil analysis. My statement is an overall assesment of all components in the car and the impact it has on wear and maintenance needs.

I spent nearly 20 years racing SCCA at the National level including a number of years in Showroom Stock, so my opinion is based on that experience, for what it's worth.
But I've sort of strayed from the oil topic......

Cheers.
Dave

NC TRACKRAT

I don't believe it's been mentioned in this thread but an important aspect is to get the engine up to temperature before shutting it down. Condensation caused by incomplete warm-ups will cause a lot of problems with plugs, oil contamination, etc. Also not mentioned is the waste of premature filter changes (which are extremely efficient in doing their job). On low mileage between oil changes, I just skip the filter changes 'til next time. IMHO, the small amount of old oil left in the filters is insignificant.

vincer77

This is Rrennlist! We don't stray heere!

I tend to agree, but the added cost of the filters is pretty small as compared with the time/trouble to do the oil change.

Kika

Something else to add to the equation, what about a car that burns a quart every 1500 miles. Assuming you add a quart every 1500 miles, at 15,000 miles you have put 10 new quarts in. The new oil obviously mixes with the old oil, but there is some percentage of new oil that gets added between full changes.

It hurts my head to think about all that, so I basically just add 1/2 quart when I need it (~1200-1500 miles) and a full change at around 5k miles. That is what I did with my last 911 (1980 SC) and it ran like a top, so I haven't deviated from that mentality, although the engineer in me thinks it is overkill.