The ramp from I-44 eastbound to I-35 southbound, which I use five days a week, sometimes six, is about a 75-degree curve that I routinely take at 60 mph unless it’s wet or the 6:30ish traffic doesn’t permit. (I’m going from a road where the speed limit is 60 to a road where the speed limit is, um, 60, so 60 seems like the most logical speed.) In fact, I consider this a test of car and/or tires: if there’s any squeal, it’s a fail.
As fast as I was willing to go on those old Dunlops was 66 mph, and the results were just this side of scary. The first trial of the Coopers yielded a satisfactory 61-mph run; I think they might go 62, maybe 63, but I won’t know that until tomorrow morning at the earliest. The Traction rating is A, which sounds good enough, though the Dunlops were AA. (I don’t touch anything with a B.)
In terms of noise, the nod goes to Cooper, but only slightly; I wasn’t carrying a sound-level meter, but my seat-of-the-pants estimate I was wearing pants is about 1.5-2 dB quieter. (By which I mean, it’s more than 1, which is barely noticeable, but less than 3, which is obvious to everyone.) And now I can quit wondering if maybe it was the wheel bearings making all that racket.
The major gain, though, is in ride quality. The Coopers carry an H speed rating (130 mph), suitable for the mission of this vehicle. (The first Car and Driver review of the model contained a top-speed figure of 131 mph. I have not tried to get within, um, let’s say 20, of that.) The Dunlops were V (149 mph), which might have been overkill; certainly the sidewalls were stiffer, and every slight, or not so slight, irregularity in the road surface was duly transmitted to the interior. The upside of that was the creation of some artificial steering feel; the helm has now returned to its original factory numbness. Then again, my personal benchmark for steering feel is my old Toyota Celica, which actually had some of it, what with its complete lack of power assist; I have recorded no seat time in, for instance, an early 911.
So for now, I’m content, and will probably remain so until my bank statement comes out, a couple weeks from now.