The following results were reported in response to the same survey, which also appeared on the e-mail lists. Duplicate responses have been excluded. Within each source, responses are shown in chronological order (oldest first). Responses are unedited except for the removal of names from those sent in private. I am including all responses, even those that note using other pressures and/or other tires.
Responses appearing on the big list:
Response 1:
Francis Gan
[email protected]
I've always run OEM pressures cold on the street. On the track, which makes up less than 2% mileagewise of treadlife, I am at the same operating pressures. I've had 2 sets of 16/17 RE010's and 1 set of 16/17 Yoko A022's. In all cases, the centers on the rears wore out first. On my current set of Yokos, I've had about 10% of the treadlife mileagewise on the track and the wear is a bit more. Of course, I'm also running Type S/Z suspension and alignment and the centers seem to not me worn as much compared to the sides.
Response 2:
DanO
[email protected]
b) center of the tread wore faster than the edges
At 38-40psi the center of my rear tires (17" OEM) wear faster even w/ some track use.
Ken, maybe your tire gauge is off calibration? I'm serious! I have 3 expensive gauges and the variation between the three is as much as 5psi.
DanO
Response 3:
Kevin Hiroshima [
[email protected]]
OK, I'll chime in on this topic. In an effot not to miss anything, my answer is "b" with the following attached comment:
On my 1991 NSX with OEM suspension and a known-good '91-spec alignment* with A022H tires, the rears would wear in the center with mostly very spirited back-road driving, and with mostly interstate driving they definately wear a strip in the middle considerably before the rest of the tire. This was with the 17" A022H rears. Lowering the pressure to about 35PSI on the rears evened out the wear for interstate driving.
ctrl c, ctrl v is the best
Kevin
Responses appearing on the tech list:
Response 4:
[email protected] [email protected]
I run 40 in the rear (33 in the front) and get a uniform wear pattern F+R. This includes sedate driving, spirited driving and track driving.
Andy
Responses sent in private:
Response 5:
Ken,
Response for me is (a).
Cheers,
Response 6:
Ken, the whole thing is a disservice to the NSX community. Increasing the rear tire pressure beyond 36 psi makes the NSX highly prone to over steer at high speeds.
Response 7:
I used to run 40# in the rear but was getting too much center tread wear. I am currently running 37# and it seems to be better. I am running the fronts at 33# and that seems to be correct for my style of driving.
Response 8:
I got (b) using the Yokos on a 99 with stock NSX-Z suspension settings.
Look forward to seeing the summary stats.
Response 9:
Hi Ken,
On my '92 with stock rear specs the OEM Yokos wear VERY evenly at 40lb pressure driven on the street. With '93+ rear specs they still wear VERY evenly at 40lb pressure driven on the street. They just last (alot) longer.
Also, I personally beleive Yokohama changed the rubber compound of the A022 somewhere along the way to a harder compound. Here is why: the A022s that came on the car went 6000 miles (any sane person (not me) would have replaced them at 5000 miles). I then went through 4 pairs of 245/45 A008RSs on the rear. These pairs went 9000, 8300, 9200, and 8600 miles. At 41100 miles I mounted a new rear pair of OEM A022s. This pair of rears went 13500 miles (significantly longer that the first pair of rear A022s).
The third pair of rear A022s were mounted at 54600 miles when Mark Basch convinced me to go with '93+ rear specs. This pair now has 20400 miles on them and there is plenty of tread left!
I have always used the same tires/wheels for both the street and the track. I use stock pressure on the street and drop pressures at the track when appropriate.
Hope this helps,
Response 10:
This is probably not a good data point, but when I bought my 16/17 USED Yokos on OEM wheels, the rears were very worn in the center. Pressures at the time were below 40. Can't vouch for how they were used. I now have new Yokos on the rear and am runing 37psi. Can't judge wear yet.
Response 11:
Ken,
"A"
Response 12:
I used the 15/16 OEM Yoko A022H on my care the previous set. I used about 28/32 psi and I got even wear, other than the inside edges wearing first. I had the car aligned years ago to the original factory specs (I have a '92).
My *opinion* is that there is NO WAY 40 psi rear would have *also* given me even wear in the rear.
Response 13:
Hi Ken,
I don't have those exact tires, but I've been using Bridgestone Potenza S02's and (later) S02PP's in combination street and track driving. I have been using recommended tire pressures.
I determine the wear three ways.
First, looking at the tread wear directly, it's pretty even except for the usual front inside edge wear.
Second, I used a RayTec infrared thermometer at the track and it said the temperature was within 5 degrees F of uniform across the treads.
Third, I have a little groove maker rotary cutting tool that you run across the tread and it makes a groove about 1 or 2 mm deep. Then you drive and then look at the groove depth, or measure it, to see if it's still uniform, or where it wore differently. Then you can make another groove after a change to see if it's better. I was told this is quite popular in NASCAR.
The 33/40 PSI recommended pressures work fine for my tires and my pattern of driving. The even wear shows the contact patch is averaging to be optimum for my driving. Again, excepting for the front inside edge thing, but that is a different issue.
Regards,
