I went in to buy new tires last Friday at the local tire shop, the one where they are running around constantly. I ordered the OEM Pirelli PZERO 255/35ZR20(97Y) 220 AA A Directional (F), and the 285/30ZR20(99Y) 220 AA A Asymmetric (R). They came in, and I had them mounted, after verbally confirming several times during the order, and after they arrived, that they were the Directional, and Asymmetric tires I had ordered, and are what is specified in the owners manual, which I had to download since it was not in the car when I bought it; I was assured they were. It was late in the day and they were closing, so I signed for the tires and left, only to get home and find that all four tires are Asymmetric, and have 'OUTSIDE' printed on each tire, front and back; the tread patterns are identical as well. However, it did handle very nicely on the way home, and cornering was unbelievable, but anything is better than the tires that came on it. Worn Toyo Asymmetric on the back, marked left and right, and two different brands of tire mounted to the front, so three different tire manufacturers total, but at least marked Directional. My question is, are the four Asymmetric tires going to have any adverse effect on the car, or handling. The tire shop is of no help by the way, longer story.

thanks,

 

IMO ...

Unless you have some extreme performance requirements, I think you'll be fine.

On dry pavement the behavior of the tires will depend on tire construction and rubber compound; tread pattern will matter little if at all. Tread patterns (excluding off road) are mostly about channeling water, and in some cases snow, so as to keep the rubber on the road. Lots of opinions of the merits of various directional and asymmetric patterns, but most patterns in use should be fine for normal driving. I think most us us would be hard-pressed to detect a difference.

 

Tire tread designs are mostly about marketing. Very high performance tires are simple ribs with perhaps a little crosscut for the outside edge. These tire are by far the quietest. Outside of winter tires everything else is pure hype.
If you think otherwise do the math, 750 revs per mile, or at 60mph 750 revs per min. Just how long is any part of the tread in contact with the road? If your tire is 12" wide, water simply can't move through those clever designs fast enough. In fact most of it is simply pushed out of the way. Real world tests show assemetric tires work just well going backwards.
There is so much myth and hype about tire tread design, if there was anything to it you'd think after 100 years of making them we would have found at least a few tread designs that actually work, but we haven't.
Notice there are no treads on racing tires, they are smooth, hence slicks. The best rain tires are ribs, just a plain slot cut into the tire every inch or so across the tread. Go to Tire Rack and check out all the "max performance summer tires"
It's more about compounds than anything else, but that's not nearly as sexy as pretty tires.
Regards,
White Bear.

 

I went through a few sets, On the 02 XKR 100 mine came with Pirelli P0 Asymmetrico/Direzionale which were very sticky/tacky and wore out on me before 10k miles. I switched to Dunlop SP5000 which were a little better than that, and wore out about 15k. Oddly enough BF Goodrich Pole Position AS which are a harder compound and have been great ever since!

I went through a similar phase on my S-Type R, went from crap Continental sportcontact 2 or whatever on that to the same BF Goodrich Pole Position AS, but they weren't as good as the cheap Nexxen's I slapped on. If you're not tracking the car don't spend the money, just grab whatever works for you.

I have Continental ProContact on my 09 XF Supercharged, and they're ok for now. Probably switch to Michelin PS or something similar, we'll see.

 

The majority of drivers (more than 98%) will most likely never test the limits of any passenger car tire. People buying Z, W & Y speed-rated tires are simply wasting their money. When was the last time anyone on this forum drove their car in excess of 150 mph? Unless you track your car regularly buy what feels right for you and also fits your budget. I have driven high-horsepower cars for years, yet rarely got over 120 mph on public roads. Handling in the "twisties" is usually governed more by weather conditions (temp., rain, snow etc.) than by your tire design.


The only time I really felt concerned was when my 300zx was in for a timing belt renewal and I was given a crap old Nissan Stanza as a dealer loaner. I was doing about 95 mph (probably near the cars max speed) on the 401 in Toronto. As I was proceeding through a switch-overpass I was cut off by an inattentive driver that crossed directly into my lane about 3 feet in front of me going at least 20 mph slower. As I yanked the steering wheel to the left the car darted to the other lane and the two right wheels lifted about a foot off of the pavement. Much to my surprise, as I immediately corrected the wheel the car surprisingly settled back down on all four tires.
That POS car with it's crappy 14" all-season tires handled the driving input just fine. I was probably somewhat lucky, but the tires did their job just fine.

 

Hello All,
Thank you all for your input. What I am really concerned about, is that the manual specifies directional on the front, and asymmetric on the back; these are the tires I had ordered, but I received four asymmetric tires instead. After having had some time to drive around on them, I am concerned with the behavior of the front end while driving. These tires have a pronounced outer edge; while this is good for cornering, I have noticed that they are also very good at throwing me in and out of the ruts in the road, without warning, and I end up feeling like I am on a carnival ride, as I am fighting the steering wheel at times, because the new front asymmetric tires want to follow the 'grooves' already established in the road. Before, when I had the previous front tires, which were directional, I did not notice this behavior. This is what concerns me about this setup of four asymmetric tires. Is this a valid concern, or something I need to get used to? Also, seasons are changing, what is the consensus on a good all season performance tire? Do Asymmetric and directional apply to these tires as well?

 

The phenomenon you describe is called trammeling. And I think there is something else in your setup causing this. I'm on the third set of P-Zero Neros in my BMW 325xi and I've not experienced trammeling to the degree that is would become an issue. IMO there is something else in your setup causing this issue.

My understanding is the primary advantage of directional tires is the evacuation of water from under the contact patch. I have recently gone to asymmetrical tires whenever possible because it offers the advantage of being able to rotate the tires, and this far outweighs the wet weather advantage. I'm not running Continental DWS All Seasons that are asymmetrical for that very reason,... to rotate out the inside front wear due to the consequences of unadjustable negative camber wear.