Valvoline VR1 Racing Full Synthetic 20W50, 1.3k mi OCI, 8k mi, C7 Corvette Z06

The UOAs don't show it but there's a lot of street (and some track) driving in between. The engine has about 8k miles on it since being built. For example, between the 7/9/22 and 6/19/21 samples the car racked up 165 engine hours and 6700 miles.

For M1 (sample 7/9/22) vs VR1 (sample 8/3/22) it was a similar OCI with a similar number of street and track hours and the VR1 did much better in wear numbers.
There are a few camps/tribes here on BITOG, and I am in the "wear numbers matter" camp. I agree with you that you can derive, assume, and assert certain things from these reports. Of course you can. Keep it up, reading with interest.

FWIW, I have never seen a 20w50 oil of any brand/quality deliver poor results, even in extreme circumstances. Usually the results are exemplary and much better than other "trusted" oils. Yes, I just made a blanket statement, fellas.
 
Last edited:
Possibly, but it's about 10-15% by volume per event, and I sample after every event for now. I try to take samples after the make-up oil has been through several drive cycles on the track, never right after adding it. I don't need to add make up oil on the street. Plus, what I am interested in is the trends not the specific values. So, as long as I maintain the same sampling methodology I think it should be comparable between oil samples.

I would argue that doing an UOA on this engine is much more vital than doing it on a street driven engine with long OCIs. In the latter case, as long as you change the oil often enough and use close enough to the OEM viscosity you'll probably be fine. In my case, if I use the wrong oil I could lose an engine in a single track event. Plus, the wear trends can tell me when it's time to start thinking about a rebuild. I doubt most street engines are rebuilt, but just replaced.
Bingo.
 
Back
Top