This ONLY applies to those who have the E89 Z4 sDrive 35i (not the 35is) with 18" or 19" wheels
The E89 Z4 sDrive 35i stock rotors are 330X24 . The Z4 sDrive 35is stock rotors are 348X30
Also the calipers on the 35i vs the 35is are also not the same . In a whole nut shell the 35i got the 330i front brakes
The 6 piston BMW Performance BBK will be the "budget upgrade kit" for the 35i
https://www.ecstuning.com/b-genuine-...m/34110444738/
Of course the brake pad sensor that comes with this BBK is not for the Z4 so you will need the OE or OEM brake pad sensor for the Z4
In addition we added SS lines, and went with the OEM 6 piston brake pads
I have advocated to see if ECS Tuning can put a kit together specifically for the 35i
Those with the 35is yes it would make sense to go with the F30 setup if not on a budget cause this BBK is not necessarily an upgrade for the 35is ie bigger calipers yes, but smaller rotors. The 6 piston BBK shown here is not compatible with a 348x30 rotor. We tested this today and it does not fit.