After 2 days and 100 miles with the Dunlop Direzza ZIIs, a few observations are in order:
|255/40/17 Dunlop Direzza ZII (left) vs. same size Dunlop Z1 (right)|
1. The ZII run approximately 10 mm wider than the model they replaced. Dunlop already had the Direzzas' width listed on their Dunlop Japan site with most sizes running 2 to 7 mm wider than indicated. For example, 265/35/18 is listed as 272 mm wide, which makes it a "legitimate" cheater tire! Looking at the stack of fours in the baove picture and the fit below makes it very likely that they Direzza ZIIs even wider than that. There is significantly more rubbing against the fender from the back of my Z4 M Coupe now when hitting even the tiniest potholes.
|275/35/18 Z1 fit (left) vs ZII (right), same car, exact same setup|
2. The ZIIs are noticeably louder than the Z1s at highway speeds. The Z1s were reasonably quiet by performance tire standards when new and only got loud toward the end of the usable life. The ZIIs have bigger, longer tread blocks and it only makes sense for them to be louder than the Z1. This won't bother those looking to buy the ZIIs mostly for track and autocross but if you are planning on running these tires in you daily driver, you may want to hear them at highway speeds first before you determine if you can live with them on daily basis.
3. Steering response in the ZII feels better compared to the generation they replaced. The steering is more direct, communicative, and it has that "right now" feel. It's really imrpessive and it's likely due to a stiffer sidewall design.
Any further comparisons (esp. lap time improvements) will have to wait till the first few track days. First autocross event is on April 14, we'll know more about the ZII's performance at that point.
Clarification: Unmounted tires run wider than mounted tires, so the actual difference in width between the ZII and Z1 is probably a lot smaller than the first picture above indicates. The ZIIs are more squared off around the shoulder for a flatter overall stance, which is why they feel like they run wider and take away clearance in the wheel well.
Related 2013 Tire Posts:
Best 2013 Performance Tire Poll
Dunlop Direzza ZII - Onboard Video at the Autocross
Dunlop Direzza ZII: The Lap Time Comparison We've All Been Waiting for!
Dunlop Star Spec Direzza ZII: A Tire as Exciting as a Date with Scarlet Johansson!
First Dunlop Direzza ZIIs Shipped to Customers!!
Bridgestone RE11A: A New Suspect Has Entered the Crime Scene