Since I can get a set of 245/45 17 Hankook tires for 400 bucks and then get a 60 buck rebate!!!

 

Edit .... oops! got numbers wrong in 1st post. Will correct and repost.

After re-think ... The 45s will have about a 4% smaller circumference, and so will introduce a corresponding error in the speedo and in the overall gear ratios. Not terrible but, IMO, better to stay with the 50s.

 

Right, looking at 245/50 17 Gmaxes atm, not much more expensive, and gotten decent reviews.

 

Your lucky in the States to have a choice, in the UK the original tyre size is rarer than rocking horse ****! One choice..... Pirelli from Italy, and they only produce 2 per annum I think
Bob

 

Your original 245-50-17" tire has a diameter of 26.8" and it takes 770 rpms per mile.
The 245-45-17" tire in question has a diameter of 24.8" and it takes 840 rpms per mile.
That's a 9% performance shortage--quite a lot.

A 225-55-17" tire essentially has the same diameter as OEM.

Otherwise, you'll be changing to 18" wheels to match the diameter. You might do best to use the OEM size tire.

I can see why TireRack stocks a million tires. There's absolutely no reason there are dozens and dozens of different tire sizes--Summer Tires, Winter Tires, Mud Tires, All Terrain Tires. We now have Chinese and other third world tires hitting the retail market, but they don't belong on a Jaguar.

There are many tire brands mentioned on this website that Jag owners are perfectly happy with. None are inexpensive, however.

My XK8 came with brand new Pirelli P7's, and I'm not at all thrilled for their ride quality at $330 (uninstalled) online. And, Jaguar spec'd an OEM tire size that's not commonly used.

 

To the rescue, General Gmax AS, $133 a pop! I'd prefer Michelin sports, but at $220 each, doesn't seem worth it.



General G-MAX AS-03

 

I get a different answer. It's about a 4% difference, not 9%.

In the tire size spec, the 1st number is the tread width in mm, the 2nd number the ratio of height to width in percent, the 3rd number the rim size in inches. Armed with that plus "1 inch = 25.4 mm", we can crunch the numbers ...

The tire diameter is given by the wheel diameter plus 2 x the sidewall height.
- for 245/50 17: diameter = 17 + (2 x .5 x 245 / 25.4) = 26.65 inches
- for 245/45 17: diameter = 17 + (2 x .45 x 245 / 25.4) = 25.68 inches
The 1st tire's diameter is 3.8% larger than the 2nd.

The circumferences and rpms-per-mile of course vary by the same percentage as the diameters.

There you go.

 

Sorry, Dennis. I took my info on diameters, etc. from Bridgestone's tire specifications as noted on Tire Rack's website. I figure they know more about the tire business than I do.

Anywhere it goes, tires are a major expense--at least when you have to replace them. Fortunately, many Jaguars are not driven as many miles as other brands of automobiles and tires may last many years.

 

Bama,

I'm thinking typo on their site maybe. A 24.8" diameter on a tire labeled as 245/45 17 would be nearly an inch away from the nominal value of 25.7

I looked at a few more tires this AM but can't find any that would be that far away from the nominal value.

IAC, I think it would be worth double-checking this if someone were thinking about buying this particular tire.


Next time out, I'm going to try like hell to rid myself of the Michelin$. 25k miles per set (if I don't drive too hard) and a four-figure price installed. Yuk!

 

Dennis
Thanks for the information. I don't think 25,000 is to bad on these cars I've heard a lot of people complaining about the life of the high performance tires, with the high performance ratings I think the tire companies do not engineer these for miles.
I've heard people complain about wearing them out in 15,000 or less.

 

Got a new set of Toyo's Luxury touring all season. Love em. More grip than the Pirellies '0's and way smoother ride yet corners like before. Talk to me in 10,000 km though.

 

Woah, Pirellis seem like overpriced POSs

 

RC,

I agree with you. 25k miles is probably an OK number for these high-performance tire.

Thing is, my driving habits don't really require such tires. My '01 has the different sizes (245/255) front and rear, and last time out I was in sort of a hurry and didn't see an alternative to the Michelins, so I just bit the bullet and bought my 2nd set. Ouch!

Next time I'm going to look harder for an alternative.

 

Dennis
I just put a set of Michelins Pilot Sport 285/30ZR20 and 255/30ZR20 replacing the Perilli's I've noticed that the car seems to handle better and is quieter. Now this could be my imagination, I wonder if anyone else has noticed a difference after replacing their Perilli's.

 

But, at least those Pirelli P7's belong on that Jaguar model.

Of course, if you prefer to buy domestic, first you have to find a domestic manufacturer, and a tire that the manufacturer does not have manufactured offshore. Tirerack shows notes on each tire and size as to where the particular tire and size is manufactured. Not many US entries in the interesting tires.

 

I replaced the stock Pirelli tires on my old XK8 coupe with Michelin tires. Good when new, but excessively noisy as they aged.

My 2000 XK8 convertible still has the stock Pirelli tires but I plan to replace them with the Continental Extreme Contact DWS tire. Several XK8 owners on the forum have recommended both the Conti and the Hankook tires. This Conti is a four-season tire, which in the Oregon rain, will serve me better. I do not trust the Pirelli tires in wet weather or below 40 degrees.

Have you priced America's Tire Company/Discount Tire? They have stores across the US and I have had great service from them. They may even match Tire Rack's price if you can work a deal. They have great installers and also do wheel repair work. (I have no business or personal relationship with this company; just a satisfied customer.)

Good luck!

 

Riken Raptors!

 

I replaced my rear tires with Pirrellis but next time I'll go with the Faulkens. I put them on my daily driver and they are fine.

 

Here's a handy tire size calculator I keep on my favorite's list: Tire size calculator
It will tell you your speedo error if you change sizes.

My car came with 245/45 ZR17 and I'm going back to 50s or 55s this fall just for the ride improvement. I spend 10-12 hours a week in this car, 95% of my time on the freeway. These tires make my speedo 3.6% fast per the calculator above and that jives with my comparisons to the freeway speedo check sections.

I'm looking at the Continental DWS. They got a good review from Reverend Sam and others on this forum, have good reviews online, and are a good price online at $161ea plus shipping and plus $20ea for road hazard warranty Discount Tires. . Just have to find someone to install them at home so that will run another $100.

That General Gmax AS is looking good at $133ea and has good reviews.

The Michelin Pilot Sport A/S Plus are running about $260 plus install out here at Costco. Not getting the best reviews, although some folks just rave about them.

The Toyo Tourevo I just priced at Les Schwabs were in the Pirelli price range at ~300ea plus install. They're aren't getting good reviews for longevity on the Prius forum.

I'm also considering some Goodyear Eagle GTs if I go for low budget. But, that would be a 235/55 ZR17 and put my speedo about 2% slow; ~ $125ea. Should be a nice ride, although some reviews aren't great.

Sorry for the epistle, I've been shopping tires for a while now.
Mike
..it's summer in the Northwet finally! ..got my sunburn with the top down yesterday...

 

On my 1997 XK8 coupe, tyre (tire) setup is:
Front Michelin MXM4 Pilot 245/50/R17 and on the rear Pirelli P Zero 245/50/R17.
No handling issues.
Rob Seignior,Australia
1997 BRG, XK8 coupe