I researched that point, and found a discussion on this forum from way back featuring boneheaddoctor, Brian Carlton, and R. Leo:
OM 603 question..............
Opinions are mixed, there was talk about too much torque for the clutches - others said “nonsense.” More and more for me it comes down to accepting the likely fact that Frankencar projects are fraught with peril. Some of them do seem tempting, such as putting a Subaru motor in a Porsche Spyder kit car such as Hoovie did.
My mechanic friend in Redwood City put an LS into a Porsche 928 which had a blown motor. It looks like good work, but the thing has been parked in the same place for a long time. I’ve never asked him if there’s some semi-fatal problem going on.