There has been a log distance test with the 190E 2.3-16 in 1983 on an oval circuit in Nardo Italy.
For 201 hours they drove without stopping at an average of approx. 250km/h.
The car was almost completely stock and the outside temperature was max. 40 degrees Celsius.
Several long distance records were broken.
av. speed: 247,939km/h
time: 201h 39min 43s
This information comes from an original German brochure which I have from my car.
1986 190E 2.3-16