I just bought an e34 from a friend and he said he uses liqui moly racing synth 10w-50 for the engine.
My mechanic was quite surprised when I told him and said I shouldn't use that, instead use real car engine oil. Still my friend is also a mechanic with years of experience on BMWs... I've read a lot about the topic and haven't seen any consensus about whether it is ok or not.
Areas of application from the description is:
Specially developed for all-season use in street, off-road and racing machines as well as ATVs, scooters and snowmobiles operated under normal to extreme conditions. Exceptionally well-suited for use with or without a wet clutch
So should I stick with it or switch to something else?