Originally Posted by
nsk040
I went with the 20mm rear bar from the convertible and the 25mm front bar from a Z4 sport package (but not M). Fit was perfect for both. The benefit of this option IMO is that it is very close to the same ratio (F/R) as stock.
Car is slightly more resistant to roll, but I'd say the difference is pretty nominal vs. stock. Most kits (TMS, ECS, etc.) have bigger bars - especially at the front - which would be more noticeable. If you want to improve rotation, maybe consider doing just the rear bar.
Install notes:
Rear - Not too bad, but getting the bar out is a pain. I took the wheels off and pulled the screw out on the top of the end-links. It would also have been helpful to remove the bushings from the bar before pulling the bar out. Having less stuff attached to the bar makes it much easier to pull out. I got the bar out by pulling through the driver side wheel well; didn't have to drop the exhaust.
Front - Much more simple. Just be sure to have a very thin wrench for the sway bar end-links.