P. Ortiz

I'm in the process of shopping for a set of maximum performance summer only tires for my 951 with the original Fuchs 7 & 8 by 16" wheels. As I compare specs, one thing that really stands-out is the difference in the weight of same-size, similar performing tires. In some cases, the difference is as much as five pounds per tire! I've always tried to look for ways to decrease unsprung weight. Is there some justification for a heavier tire? Maybe a stiffer sidewall for better response? But still...five pounds per tire?

Jim Michaels

A five pound difference is a lot. I usually see only 1 to 3# difference when comparing tires. Are you sure that you didn't include some Hoosiers by mistake? Some brands seem to build somewhat lighter tires across the board, but not usually by that much. Somewhat thicker sidewalls could probably add as much as a couple of pounds. Then it's a question of whether the additional sidewall stiffness can cancel out the additional unsprung rotating mass.

P. Ortiz

Two of the tires I'm looking at are the Continental Extreme Contact DW (21 lbs.) and the Bridgestone RE050a pole position (26 lbs.). Those weights use the rear tiress (225/50-16) for comparison. I'm leaning toward the Bridgestones because the Continental seemed to get consistent reviews reporting less responsiveness and feel, but it's hard to ignore such a big difference in weight.

Jim Michaels

From my brief visit at the Tire Rack site, it looks like you've honed in on two good ones. There is no head-to-head test comparison, but the survey results seem to indicate that the Bridgestone has the edge in steering response, while the Conti has the edge in wet traction, ride and noise comfort, tread wear (it's a 340 vs a 280), weight (21# vs 26), and "would buy again." The Conti finished 3rd in the head-to-head tests that included GY Eagle F1 (2nd), Michelin PS2 (1st), and P Zero (4th).

P. Ortiz

Thanks Jim, for your interest in my post and for taking the time to check the information at Tirerack. Both the re050a's and the Conti's pose compelling reasons for choosing each. I really want the best steering response possible, but when I see the 5 pound difference I think of all the people who carefully choose new wheels based on saving a couple of pounds. I see the Conti's as the path to lightness, the easy way. Oh...I'll get through this.

Regards,
Pablo

Jim Michaels

You're very welcome, but I'm just trying to substitute for the much better informed Damon at Tire Rack. Sometimes he chimes in on tire threads here, and maybe he still will if he spots this thread. If not, you can contact him directly at Tire Rack. If you call on the phone, his extension is 643.

Tires are so complex and specialized now that I have trouble keeping current; especially with new tires coming onto the market so frequently. It's a very competitive market; that's a good thing for the consumer, but we also have to be better informed in order to choose wisely to best suit our needs.

Regarding unsprung rotating mass, extra tire weight is probably worse than the same extra weight at the wheel because the extra tire weight is farther out from the center of rotation. Thus, shaving track tires not only reduces squirm and provides a little more rubber contact, it also removes a couple of pounds from the worst place; the outer edge.