We recently used our shop's F10 M5 for a ACS (Fontana Roval) track day event and quickly found a slight issue with a stock oil cooling setup. The vehicle has all stock hardware with exception of water injection and our stage 1 flash set to 24psi limit. At 108F degree weather, we ran into oil temperatures being as high as 138C (280F) at the back straight doing 150mph+ passes after just 2 or 3 hot laps. This was causing safety functions to come in and cut power dramatically in order to save the motor.
Interestingly enough, the cluster gauge stayed at 240F the entire time BUT data log of actual oil temps showed 280F temps between turn 20 and turn 2. Shows you how accurate our gauges are...So, if you are tracking your M5, consider running a dataloger.
This continued for 3 sessions at which we were forced to get the car back to the shop (due to a slight technical issue with tires).
Now we are re-doing the oil cooling system with an additional head exchanger to try and combat this issue. Will have the final setup posted here once the parts are all done sometime next week, followed by anther track day/datalog mid august.
Little clip from the Backstright run: