Hey guys,
Under the picture of the Bridgestone Duelers is this note: Load-Speed Rating/OEM Fitment: 105T. That indicates 'T' rating (118). And, there is no matching tire that will fit the front.
I must not be making my point clear. I (and many of you) want to find a full set of tires that will fit 15" rims on a Cobra and work properly. Manufacturers will not sell us a car that will go faster than the tires are rated. For instance, if you buy a new Mustang with 'S' rated tires (112 mph), the computer will prevent you from driving faster than 108 mph. I know, I rented one!
Our cars do not have limits set by computers (mostly). With the power to weight ratio of a Cobra, the top speed is limited by either the gear ratio or aerodynamics. With my tremec 5 speed, my car will theoretically do 195 mph at redline. Practically, it will do 140 very nicely. If a tire comes apart at that speed....well just take a look at the Silver States Classic open road race, people get killed.
I would love to buy 'Z' rated tires and not worry any more. But, nobody sells them for 15" rims. The best I can find are pure racing tires that are expensive ($600 to $1,200 per set) with very little tread. They last a few thousand miles and then you have to buy another set. I want tires that I can afford and that will last for a year or maybe two and that I feel safe with at 100 plus in the middle of nowhere. I visit there often.
The Ford Lightning truck stimulated tire manufacturers to produce a better 15"tire. There are only a few that are 'H' rated (130 mph) that will fit the rear of the Cobra but none that fit the front correctly. For instance, the Toyo Proxy S/T is 'H' rated and comes in two 15" sizes. The 275/60/15 and the 295/50/15. Either one fits the rear of the Cobra fine. However the 275 is more than an inch taller than the 295 so you don't want to run the 275 on the front and the 295 on the rear because the rake of the car will be nose up. The best I have been able to do is run the 275s all around.
The significance of the new Kumho tire is that you will be able to run 255/60/15s in the front and 275/60/15s in the rear and everything should fit correctly, give nose down attitude and be safe, up to the practical limits of the car. They also have stiff sidewalls (read good handling) and great traction ratings.
If you feel that this is not important, fine. To me, it is a matter of life or death, I drive pretty fast. We are driving cars that rival the best world class supercars in performance. To actually use that performance, and live to tell about it, you need the right tires.
Paul