With the release of the Z4 35is BMW will be offering only one transmission; the DCT. Our understanding is that the manual 6 speed Z4 (specifically the clutch) can ‘t handle the torque that comes with the engine upgrade in the car. And we ‘ve seen this issue previously with the 135i/335i BMW Performance engine kit. In that car torque was increased to 332ft-lbs in the auto but only 317ft-lbs in the manual.

So it would seem that for BMW to offer the Z4 35is in a manual set-up they would have had to engineer an entirely new manual transmission. However given the current economic conditions they likely weren ‘t willing to go that route. So the DCT by default has become the only option. Granted BMW faced this issue before with the E46 ZHP when they added a close ratio 6 speed – the first to a non-M 3 Series

The bigger question is, will this be a trend with BMW? We know that this engine and this trim level will show up in other BMWs (more info to come soon) over the course of the next two years. Are they destined for the DCT only as well? And why didn ‘t BMW spec a box and clutch that could only handle 317ft lbs of torque and then use it across their entire range? Did the folks in BMW sourcing not know that the twin turbo six would eventually be upgraded? Or is there a new manual transmission and/or clutch coming soon that will solve this issue? All questions we ‘ll likely get answers to over the next few weeks.