The Tire Review section contains info on specific tires

What Are The OEM Tire Specs?

[KS, DB, RW, HS, FG, AT, GM, A/H]

Most cars came with Yokohama A-022H tires (A-022H1 for '91-'93 and A-022H0 for '94+). Some cars came with Bridgestone RE010.  Both of these tire models were developed specifically for the NSX.

OEM tires work with the NSX suspension to promote scuffing of the contact patch even when the car is traveling straight. The rears toe in and the fronts toe out slightly, poising the car for instant response and direct steering feel.

Combined with directional tread patterns this results in 4 different part numbers for the tires located at the 4 corners of the car. As far as I know, no other car is so equipped.

What Makes OEM Tires Different?

[GM] Only OEM Bridgestone RE010, Yokohoma A022H and Dunlop SP8050 are constructed with the internal plys angled to scuff sideways (ply steer) when the car is driving in a straight line. This helps give the car its precise turn-in characteristics. Other tires may have other qualities, but I would not describe them as almost identical to OEM tires.

[KS] There are three tires that are made specifically for the NSX: Yokohama A-022H, Bridgestone RE010, and Dunlop SP8050. All three are designed to  maximize the handling and precise turn-in of the car. All three wear fairly quickly, have outstanding dry traction, and not very good wet traction. Numerous list members have reported that the Yokohama's have the best handling and traction of these three tires.

Other tires will not have the precise feel on turn-in that these three tires do. However, all other factors depend on the tire. For example, as a general rule, track tires (like the Goodrich R1 or Yokohama A032R) will actually have LESS tread life than the NSX-specific tires, and better dry traction (quicker lap times). OTOH, some list members have switched to
non-NSX-specific street tires, particularly the Dunlop SP8000, because they want longer tread life and better wet traction than those, and are willing to sacrifice dry performance and handling. Note that Dunlop has a new line, the SP9000, which will eventually replace the SP8000 and is reported to have even better tread life and wet and dry traction than the SP8000.

[Michael F. Hollander, Yokohama Tire Specialist] Here's some additional information from our Technical Department:

The compound of the front and rear NSX tires are slightly different in grip level. In addition to the compound, there are numerous construction and tread profile differences between the tires. These differences are necessary to work with the design of the suspension to give the target handling requested by the vehicle maker.

UTQG tradwear ratings are based on a tires wear performance against a standard monitoring tire chosen by the US Government. The manufacturer chooses the exact rating to use based on testing data received for the compound used. Although the grip level of the compounds used for the front and rear of the NSX is different, the result of the test against the course monitoring tire were relatively close. As the ratings used by manufacturers is normally conservative, the tires could be rated the same to avoid confusion for the uninformed customer.

Compounds can be made today to have different grip levels but be relatively close in wear characteristics. Although the grip level of the front and rear tires is different, ti is not a large change from one to the other. The request from Acura was to help stabilize the car during high speed cornering and assist with the development of a slight understeer condition. To accomplish this, the rear tires are constructed to add a "toe in" effect in the rear as well as generate more grip in the rear than in the front to give "understeer". The compound grip change to make this happen was small, resulting in relatively close UTQG ratings.

[DHW - 99/9/16] There was a change in compound of the OEM Yokohamas according to George Lugo at NSXPO'97. The compound was made a little bit harder (10%?) to address the "premature tire wear" concern that was brought out in the early years.

What Special Considerations Do OEM Tires Require?

ALL factory tires are corner-specific (meaning they cannot be rotated).  Do NOT let anyone rotate your stock tires. Also, Yokohama A022 tires for the NSX have built in bias - the fronts pull to the outside and the rears pull to the inside. Therefore if you mix a normal (RX-7) A022 with a A022H (NSX tire) you may get some handling surprises.

Factory tires for the NSX wear out quickly. There are several reasons for rapid (not necessarily excessive) tire wear. factory tires are a very soft, sticky compound. '91-'93 NSX's with Yokos driven on the street (not racetrack) typically get 5,000-8,000 miles to a set of rear A-022H tires, and usually at least double that for front tires. The '94+ models came with 16 inch front and 17 inch rear tires which last a little longer.

The front tires tend to wear out first on the inside. Turn the steering wheel all the way to one side to inspect the full width of the tread. This wear is caused by both the toe-out and negative camber of the front end. See Tires and Wheels - Alignment for more discussion of alignment.

[BZ] I just put 4 new A022s on my car. I watched the guy as he mounted the tires and caught him doing it incorrectly. I.E. he put the left tire on the wheel headed for the right side. He assumed the arrows are on the outside. He was half right. There are arrows are on *both* sides of the A022s. They are labeled "SIDE FACING OUTWARDS" and "SIDE FACING INWARDS" .

[KS] When the Yokohama A022H are new, they have a HUGE colored sticker on the tread that says (for example) RIGHT REAR. The sticker is triangle shaped with an arrow at the point of the triangle that says ROTATION.

[JS] My only experience has been with the yokos. Once wear begins to approach the wear bars, the wear rate seems to increase exponentially. You can go from the wear bars to cord in a few hundred miles. Similarly, handling becomes squirrelly and unpredictable. Tread lightly my friend!

How Can I Improve Tire Life?

[KS] Some owners are quite happy with the performance of these tires and don't mind how long they last. For those who feel otherwise, there are several ways to get longer tread life.

Alignment

[KS] One is to use the '93 and later alignment specs, which can be used on any year NSX (see Tires and Wheels - Alignment). The alignment for '91-92 was set to maximize handling and cornering capability. In later years this was changed, in part to reduce tire wear.

Tires

Another way to get longer tread life is to switch to a different model tire (see Tire Reviews). Any tire is a compromise among tread life, dry traction, wet traction, handling, price, etc. The Yokohama A-022H was designed to maximize precision in handling with outstanding performance on dry pavement, while accepting a sacrifice in tread life. Some other tires will give greater tread life and wet traction while experiencing reduced handling and dry traction.

[HM] I was told by the Yokohama guy at NSXPO 97 that the bigger tires WILL last longer. His reason: Bigger tires can handle the load better than smaller tires. My 17 rears went 12,000 miles and that included two track events. My 16" fronts have 16,500 miles on them and still look great. BTW, I even changed my aligment BACK to the original tire eating specs.

Inflation Pressure

[LE - 99/11/26] It is my experience that stock pressures (40 rear, 33 front) are too high for even tread wear on the Yoko A022H's if you don't push the car a little. If you are pushing the car the tires will wear more evenly. Obviously Honda was expecting the car to be driven hard versus logging lots of highway miles when they came up with the pressure recommendations. This is along the same lines as the the front camber angle being too aggressive and wearing the inside edge of the front tires if you are not pushing the car much.

If you drive it harder through turns on a regular basis you'll find the wear evens out. Or you can lower the pressure. I drop mine to around 30-31 front, 35-37 rear when I'm planning to do a lot of Interstate driving.

How Do The OEM Yokos and Bridgestones Compare?

I did a back to back comparison of an NSX with Bridgestones vs one with the Yokos. Both had about 50% tread left. The Yokos seem to have stiffer sidewalls and a slightly harsher ride but in return, the turn in is slightly sharper. The yokos do seem to be slightly quieter, though not by much.

The Bridgestones are more compliant in their ride and the car actually feels "softer" and more substantial as a result. Did not have an opportunity to test the yokos at the limit.

[FG] Bridgestone RE010, 12,000 miles inc. 100 track miles. Driven reasonably hard (including cloverleaf ramp laps for fun, mostly redlined 1st and 2nd gear shifts, most turns at 8/10ths) Fronts: Worn on the inside - barely visible tread blocks, outside still with about 3/16 left. Rears: even wear, 1/8" left.

[FG] OK folks, I just spent the afternoon being my own test driver and pit crew. I managed to get an extra set of 16/17 OEM wheels with Yoko A022 on them. My normal set are RE010s that came with the car. Both sets of tires have about the same wear on them - my est. 5000 miles.

Given that I do not have the capability to do instrumented testing, I can only give you my subjective ratings.

Conditions: Temp. about 78 degrees. 70% humidity, partly cloudy. Venue: some curvy roads near my house that I use everyday and some cloverleaf ramps.

First thing that I noticed after switching to the A022 was that they were noisier - particularly with the top off and windows down. With the top on and on the highway, you can tell they are noisier only if you do a back to back comparison.

The A022 was more confidence inspiring - they just provided a tad more feedback. I think their friction curve is more linear compared to the RE010 that are more progressive. However, near the limit, the A022 dropped off more rapidly though still with very good feedback. The RE010 lacks the feedback at the limit and you feel like the car could just suddenly go (not that this is the case - it just feels that way). I would say in terms of ultimate cornering grip, the RE010 is probably a tad better (contrary to popular belief, though this theory is supported by some feedback from another list member from Japan). However, I think I would feel much better driving near the limit with the A022. Just as a sidenote, the A032R on 15/16 that I use for the track isn't very confidence inspiring despite the higher adhesion limit.

Road comfort/compliance in the A022 seemed to be better - this is not to say that the A022 has a softer sidewall. It could be that the tire spring rate is better suited to the suspension on my T. From what I can remember, the A022 on a coupe with 15/16 wheels felt harsher than my setup on the T (probably due to the suspension differences).

[DG] A couple days ago I drove a '95 T with the RE010's for a list member from another state who's considering buying it. Although I didn't do as much of a "side-by-side" comparison as Francis did, I MOSTLY agree with his observations (my car has the Yokos): the Yokos feel more nimble and responsive, and a little more "abrupt" at the limit, whereas the RE010s have more progressive characteristics at the limit. I don't think the RE010s grip better, however: but I could see how it might be possible to reach that conclusion because of the more progressive approach to the limit than the Yokos.

[SW - 99/7/20] My car came with Yoko's A022's (16/17's) and this is my first experience with them. I've always run the Bridgestone RE010's and in comparison find them a little more driver friendly in overall ride and performance -maybe a better balance for everyday driving.

The Yoko's seem pretty sensitive and unforgiving-I mean every groove and rut makes the car track into them. The Bridgestones didn't seem to react so abruptly. I'm Running 33F and 38R and the higher the pressure the more sensitive they get.

What Are The OEM Tire Part Numbers/Prices?

Yokohama Part Numbers ('94-'97):  Left Front: 02210,  Right Front: 02211,   Left Rear: 02212,  Right Rear: 02213

Current prices from Tire Rack for '91-'93 stock sizes (205/50ZR-15 and 225/50ZR-16) are as follows:

What Aftermarket Sizes Should I Use?

How wide a tire can I put on X rim?

[KZ - 2000/7/6] Multiply the rim width by 25.4 and then by 1.1 and 1.3. For an eight inch rim that would give you a range of 223 - 264. BUT, you're not done yet. If the aspect ratio is on the low side (35 - 45) you will need to stay close to the bottom of the range. This will be the case with the NSX. If it's for another car with smaller rims and tires with aspect ratios of 50 - 70 you can creep up to the top of the range.

Profile

[BP] As for low profile tires. I talked in depth with several racers and they all agree that lower profile tires look cool, but handle unpredictably. At the corning limits of your car, you will "feel" the tires getting "lose" with a higher profile tire before they actually let go. The lower profile tires give little warning to a possible spin. I can attest to that!!! Also, higher profile tires flex in the turns which allows more tire patch to make contact with the road surface. This is why NASCAR, F1, IRL, etc... run high profile tires.

Here is what is available and what will fit the 17/18 wheel combo according to my tire source: 

FRONT:
STOCK: 205/50-15 = 23.0709" tall
STOCK: 215/45-16 = 23.6181" tall
ACCEPTABLE SIZES:
225/40-16 = 23.0866" tall (Dunlop SP8000's only $100 each)
215/40-17 = 23.7716" tall (Yoko AVS, about $145 each)

REAR:
STOCK: 225/50-16 = 24.8583" tall
STOCK: 245/40-17 = 24.7165" tall
ACCEPTABLE SIZES:
255/40-17 = 25.0315" tall (too many to list that are avalible)
255/35-18 = 25.0275" tall (Yoko AVS, about $300 each)

Reported Results

[DH] The widest that will fit on the front without major rubbing is 235/45-17. With the 245/45-17 fronts, the suspension needs to be raised a little.

[TS] Have Eibach springs (1.5" lower) with 225/35/17 and 285/30/18 and no rubbing at all. Rims are 8 and 10 inches wide.

The Chart!

How Will Different Tires Affect The Handling?

[BSD] Regarding switching tires and oversteer/understeer... this is clearly a highly technical issue. The answer is a definite "yes", that tire compounds can make a big difference in the oversteer/understeer characteristics of the car.

What happens if you switch from the stock issue tires to some other type? The first thing that came to my mind is that the stock tires are specifically designed for the NSX such that the rear tires have a softer compound so that they will have more grip. This is partly why the stock tires wear out so fast in the rear. By having different compounds in the front vs the back, the designers were able to affect the steering characteristics of the car in this way. Softer in back means more grip in back and, therefore, less oversteer (or more understeer, depending on how you look it it.)

If you switch to a set of tires that are equal in grip all the way around and are equal in grip to the stock front tires, then you have, in essence, reduced the grip in the back and increased oversteer. I would not imagine that many street tires have more grip than the stock issue tires for the rear. However, I do bet that the new generation of ultra-performance tires (such as the MXX3, Pilot, S02, etc) may have more grip.

Let's finish this discussion considering a car that has the same size and compound tires on all four corners. As that car corners, the front end gets a certain amount of grip based on the car design as well as the tire choice. Part of this grip is based on the fact that weight transfers to the front during turning and a lot of weight can transfer to the front outside tire giving it lots of grip. At the same time, weight is reduced from the rear of the car which reduces the available grip back there. The car in question will have a steering characteristic from way understeer to way oversteer or somewhere in the
middle.

If you increase the grip at all four corners, do things stay the same? Nope. By increasing grip on all four corners, the front tires will be able to turn sharper than they used to. This causes several things, one of them being more weight transfer to the front and away from the rear. This further increases the grip the front can get and, likewise, reduces the grip in the rear. Therefore, more grippy tires on all four corners increases oversteer. If you drive near the limits of your vehicle on a
road racing circuit and have tried street versus "race" tires, you will notice that the car is more likely to oversteer with the grippy tires on.

If you have read this far, they you may be interested in thinking of what the converse of all this is... switching from racey tires to street tires or maybe considering what happens when even racey tires lose grip such as when it rains.

What Tire Pressure Should I Use?

[BSD]  On the street, there are often other goals for your tires. My goals are:

1. Maximum life
2. Comfortable ride
3. Wet traction (it does not rain much in Dallas)
4. Overall performance

To attain maximum life, you will need to keep a close eye on your tires. Check them every 4k miles or so. If the middle is wearing too much, lower the pressuer a few pounds. If the edges (either) is wearing too much, raise the pressure.

On the street, less pressure (compared to the track) will result in longer tire life and a softer ride.

How do tires affect steering feel?

Here is how the steering response rates (beginning from sharpest steering response to least sharp):

94+ wheels with Yoko A-022H
94+ wheels with Bridgestone RE010
91-93 wheels with Yoko A-022Hs
91-93 wheels with Pirelli P210s.

What About Mileage Warranties?

[DN] I went to NTW and the salesperson swore that the SP8000 warranty would apply, and when I repeatedly asked for confirmation, they did confirm that it would be honored. When I asked for something written, they simply pointed to a small "30" on the printed receipt, and stated that "not to worry, it's printed right here on the invoice. See? This '30' means that it is covered by a 30,000 mile treadlife warranty."

So, of course, 7,000 miles or so later, I show up and they say "Hey, no way." A HUGE argument ensued, and we finally agreed that if they covered the tires this time, I'd forego coming back again.

BTW, *this* they made certain to put in writing, of every sheet of paper involved in the transaction.

[BLW]  Some time back this list discussed the allegations of a 30,000 mile tread wearout warranty from the Sear's owned NTB (once upon a time, NTW) for theDunlop SP8000s. Being on the verge of needing four new tires, and not being sure that I'd get them for free, I decided to investigate these allegations.

There is indeed such a warranty. It provides for a straight line prorated replacement price or refund. There are some conditions (primarily, rotations) and limitations (excessive wear not caused by improper alignment, inflation, racing, etc.) but all are logical and normal.

However, being the picky attorney I am paid to be, I requested that we (store manager and I) have a discussion now rather than an arguement later. So, after many assurances from the salesperson that this warranty would apply to an NSX (along with his total disbelief that a car would only get 5,000 to 7,000 per rear tire, to the amusement of some of the knowledgeable customers in the shop at the time), the manager stated that such warranty does not apply to any car where tires cannot be rotated, and that they wouldn't honor the warranty on the NSX.

While the written warranty does not contain such a disclaimer or exception, NTB's practice does. I don't blame them for not wanting to sell me 8 rear tires and 4 front tires for only $1,000. I do blame them for shoddy business practices by not putting all of their warranty conditions in writing.

In addition, their "best" price on the tires was still $130 more than Tire Rack's.    Thought you'd like to know.

[MB] We purchased two Dunlop 8000s from NTB with the 30,000 warrany. After 6,000 they honored the warrany without a question, HOWEVER the warranty we got for the Yokos that replaced them was for 20,000 miles, not 30. Overall we are very satisfied with them, and will continue to use them for all of our cars. Believe it or not, my Prelude VTEC doesn't get more than about 10,000 miles when I have Dunlop 4000s (Z rated) on the front.

How Should Tires Be Stored?

[LE] Tire Rack told me that if you store them flat on their side and un-mounted in a cool, dry place with no sunlight (i.e. dry basement), tires have a shelf life of about 8 years. Wrapping them in big plastic trash bags helps.