///M-Spec
Staff Emeritus
- 4,928
Sure. The original high-rez version is at the office at the moment. I'll upload it tomorrow morning.
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Are they the 'run-flats' that BMW are insisting on putting on all cars or do 'M' get their own way with tyre choice?
No, they are not runflats. There is no runflat version of the SportContact that I'm aware of. Which is good because I shudder to think how much worse it can be.
M cars are all fitted with traditional non-RF tires. There is no spare, so in case of a puncture, BMW gives all M cars lifetime roadside assistance and an M Mobility Kit, which is just a sealant and compressor kit.
Some of the other ways the M version of the Z4 differ from standard.
-Z4 M has a traditional hydraulic steering rack, instead of electric assist
-Z4 M has no intake 'resonator' box that "pipes in engine sound" into the cabin
-Z4 M has a one switch off for stability control, instead of standard two stage system non Ms have
-Z4 M has a true mechanical limited slip differential (M-diff) Standard Z4 has an open diff and relies on DSC to control slip.
M