If there is oil on the stick you've got plenty for everything but sustained autocross. All that is necessary is that the oil pump pick-up stay submerged. Jim is right about the use of oil to cool the motor. Since MBs are designed for use where there are no speed limits the safety factor here easily covers any normal illegal driving for us. The fact that you have a 240D might stretch that issue in the mountains.
Bosch Master, ASE Master, L1
33 years MB technician