Thanks for your explanations.
Then I´ll look for a Z3 4 Cyl steering rack
Edit:
I looked up the steering rack at the online spare parts catalog. The steering racks are the same at the "normal" Z3, no matter if it has a M43, M52 or M54 engine.
So a steering rack from a non-M Z3 would have 2.75 turns from lock to lock?
The part number is 32 13 1 095 575.
Am I right?