Got the 255-50-16 Kumhos!

[landtodd]

I did it! Bought the 255-50-16 Kumhos Saturday, mounted them on the 16x8.5" 300ZXTT wheels (set of 4 rears). Discount Tire says they match published prices, and they pretty much did. They started at $127 a tire, but matched TireRack's price and came off their price $40 a corner. They then added $16 "shipping," so the price I paid was the "delivered to your door" Tirerack price. I saved only about $100 over Discount's list price, but that bought the out-the-door price below the magic $600 mark. That price included force-matching on the Hunter 9700, lifetime road-hazard warranty, lifetime balance and rotation, and $50 for Governor Jeb. Plus, A) they "test mounted" the tire to be sure I wasn't completely crazy, B) I wanted a local dealer to complain to, and C) there's that "instant gratification" thing to consider about going down and getting them in an hour.

Discount claimed they would reject any tire with 20# force variance, but also said their 9700 wasn't hooked up to a printer, so I couldn't get the printout. Hmmm . . . I think I'll take them in next week and ask them to check that. Very little balance weight on any of the tires.

For the first 50 miles, I'm driving pretty gingerly. Self-imposed break-in. I haven't had them over 45 yet because I've been "in-town" since I got them. Initial impressions -- my old tires were hard as rocks. These are noticably more supple. They're a little "wandery," (tramlining?) but my toe-in is off, based on how the last set wore. No real cornering impressions yet, but I installed the Q45a sway bar a while back.

The 300ZXTT wheels with the 255 tires look great on the car, much better than I expected. I'll post some pix shortly. My dowdy green Q suddenly looks a *lot* more like the sports sedan it really is. More muscular, aggressive stance. Adds a little tension to the design and even helps that dated forest green color look more attractive. I didn't check the difference in offset between my stock Inf wheels and the ZXs, but it seems like the whole extra inch of width is on the outside. (I went up 30mm from my 225s.)

Gksea reported some mild interference with 245s on the 16x7.5" 300ZXTT wheels (set of 4 fronts). I haven't locked mine over to test, but so far, no interference problems with the big Ks. Discount thought I might be a little crazy because 245 was the biggest step up they showed on the computer. I understand their caution, what with the various combinations of wheel widths, offsets, and tire sections that could crop up.

HighwayQ45 said that the tramlining was reduced in his 245s when he went up to 37 psi front. Savakus said that he got the best wear from his 245s with 40 psi in front, 35 rear. I'm trying various combinations and watching the wear with a tread-depth indicator. The 255s are 99 load-rated (1709 lbs @ 44 psi).

The mysterious red dot is visible on each of my driver's side tires. Mysterious because according to the Hunter website, the color of "the dot" differs manufacturer to manufacturer, and the location differs as to whether the dot is the point of highest or lowest radial force. Or even highest or lowest weight. "My" dots are now approx. 180 degrees away from the valve stems on each driver's side wheel after the Hunter force-matching bit.

Cautiously pleased, but really tickled,-Todd

[greg_atlanta]

Drive 'em hard!

What's the treadwear rating?

I'd aim for a lower psi, esp in warm weather. I kept my Yokohama AVS dB 225/60/15 at 38 psi all winter but just dropped them to 34 psi and they feel so much better.

I used 30 psi in my Yokohama AVS Intermediate from last summer (36 max).

[maxnix]

What is the psi for maximum load capacity? I bet it's 51 psi, which means you will want to actually run them at a higher psi to get the same reserve load capacity.

Maybe Dennis will correct me.

[Q45tech]

1709@44 or 38.9 pounds per psi............minimum cold [setting overnight measured before driven] psi would be 31 psi all around...........that way you are setting each tire for 1200 pound static load.

Since you have rear 20 mm bar that would be where I would start...........add 1.0 psi per extra passanger above driver.

A Lot really depends on alignment.........and shocks.

Get them rebalanced at 500 miles as they may slip on new rims from mounting lubricant and braking/acceleration.

20 pounds of radial force is a lot [Infiniti spec on new Q is 14 pounds or less] many Michelins I checked after optimization are at 5 pounds.

20/123=0.1626" that is the amount the tire is pushing the suspension up and down from not being round, of course new shocks can help restrict this but on smooth roads even 14 pounds is annoying on a lux car with soft springs.

[landtodd]

Treadwear is 280. They also make an Ecsta MX, which is at least as good as the other "ultra high performance" tires on the market according to Road&Track. They're rated at 220 treadwear.

Max pressure for the 712s is 44. Load range is 99.

Yup, 20# is high, but at least they promised to *reject* at that level. That's a better promise/deal than I got anywhere else. Other than dealerships, Discount has about the only Hunter 9700s in town.

When you force-match, Discount uses a paste instead of the usual mounting lube. They say the tires won't slip. (Okay, if they admit that lube slips, why not use the paste all the time? Odd. Maybe it's an added inducement to buy the premium service.) I was already planning a 500-mile checkup.