You know a lot of the SRT8 members are testing and running their cars at high speeds.... not just the short 1/4 mile. Since the Vredestein tires came out they have laid down quite a following. They are also....most importantly correctly rated for our cars with a "Y" at 186mph. There is also a "(Y)" rated at 186+mph. A "W" (168mph) could also be tolerated for short periods....maybe... How much damage is done during 170-180mph and faster sprints on "W" tires in regards to life of tire? The BFG KDW is only rated a "V" at 149! The Toyo Proxes 4 are fair with a "W" rating. The GoodYear RS-A tires some of us got with our cars are "V" (149mph) rated! The Goodyear F1 Supercar tires, some of us were lucky enough to get on our cars, are "Z" rated but I believe they have been displayed with a corrected "Y" rating. In Regards to the "Z" rating: "When Z-speed rated tires were first introduced, they were thought to reflect the highest tire speed rating that would ever be required, in excess of 240 km/h or 149 mph. While Z-speed rated tires are capable of speeds in excess of 149 mph, how far above 149 mph was not identified. That ultimately caused the automotive industry to add W- and Y-speed ratings to identify the tires that meet the needs of new vehicles that have extremely high top-speed capabilities." I am fairly sure the speed limiter on the 5.7 Hemis is set lower than the SRT8 mainly due to tire rating. Because a lot of us are and were influenced by what we read on forums that are geared mainly to the 5.7 Hemi, some of these lower rated tires have gained influence with us....but this "Speed Rating" is a very important rating to follow for the SRT8 owner when he buys tires. I mean we do want to keep our cars at the minimum to meet "SRT" specifications. I want anything I put on my SRT8 to either "meet or exceed" original specifications. I mean that is what the purpose of mods means.....right?
Information of interest from tiresplus.com. *************************************************************** Speed Rating: In Europe highways do not have speed limits and high speed driving is permitted. Speed ratings were established to match the speed capability of tires with the top speed capability of the vehicles to which they are applied. Speed ratings are established in kilometers per hour and subsequently converted to miles per hour (which explains why speed ratings appear established at "unusual" mile per hour increments). Despite the tire manufacturer's ability to manufacturer tires capable of high speeds, none of them recommend the use of their products in excess of legal speed limits. Speed ratings are based on laboratory tests where the tire is pressed against a large diameter metal drum to reflect its appropriate load, and run at ever increasing speeds (in 6.2 mph steps in 10 minute increments) until the tire's required speed has been met. It is important to note that speed ratings only apply to tires that have not been damaged, altered, under-inflated or overloaded. Additionally, most tire manufacturers maintain that a tire that has been cut or punctured no longer retains the tire manufacturer's original speed rating, even after being repaired because the tire manufacturer can't control the quality of the repair. Over the years, tire speed rating symbols have been marked on tires in any of three ways shown in the following examples: 225/50SR16 225/50SR16 89S or 225/50R16 89S Each of these was an acceptable method of identifying speed ratings. Early tires had their speed rating symbol shown "within" the tire size, such as 225/50SR16. Tires using this type of branding were not to have been produced after 1991. 225/50SR16 112 mph, 180 km/h 225/50HR16 130, 210 km/h 225/50VR16 in excess of 130 mph, 210 km/h Beginning in 1991, the speed symbol denoting a fixed maximum speed capability of new tires must be shown only in the speed rating portion of the tire's service description, such as 225/50R16 89S. The most common tire speed rating symbols, maximum speeds and typical applications are shown below: M= 81 mph 130 km/h N= 87 mph 140km/h Temporary Spare Tires P= 93 mph 150 km/h Q= 99 mph 160 km/h Studless & Studdable Winter Tires R= 106 mph 170 km/h H.D. Light Truck Tires S= 112 mph 180 km/h Family Sedans & Vans T= 118 mph 190 km/h Family Sedans & Vans U= 124 mph 200 km/h H= 130 mph 210 km/h Sport Sedans & Coupes V= 149 mph 240 km/h Sport Sedans, Coupes & Sports Cars When Z-speed rated tires were first introduced, they were thought to reflect the highest tire speed rating that would ever be required, in excess of 240 km/h or 149 mph. While Z-speed rated tires are capable of speeds in excess of 149 mph, how far above 149 mph was not identified. That ultimately caused the automotive industry to add W- and Y-speed ratings to identify the tires that meet the needs of new vehicles that have extremely high top-speed capabilities. W= 168 mph 270 km/h Exotic Sports Cars Y= 186 mph 300 km/h Exotic Sports Cars While a Z-speed rating still often appears in the tire size designation of these tires, such as 225/50ZR16 91W, the Z in the size signifies a maximum speed capability in excess of 149 mph, 240 km/h; the W in the service description indicates the tire's 168 mph, 270 km/h maximum speed. 225/50ZR16 in excess of 149 mph, 240 km/h 205/45ZR17 88W 168 mph, 270 km/h 285/35ZR19 99Y 186 mph, 300 km/h Most recently, when the Y-speed rating indicated in a service description is enclosed in parentheses, such as 285/35ZR19 (99Y), the top speed of the tire has been tested in excess of 186 mph, 300 km/h indicated by the service description as shown below: 285/35ZR19 99Y 186 mph, 300 km/h 285/35ZR19 (99Y) in excess of 186 mph, 300 km/h As vehicles have increased their top speeds into Autobahn-only ranges, the tire speed ratings have evolved to better identify the tires capability, allowing drivers to match the speed of their tires with the top speed of their vehicle. ****************************************************************
Nathan dont forget about the Falken FK452's I loooove these tires, and were great on the roadcourse...Z rated howver the load/speed rating according to Falken for the 255/45/20 is 105/Y so they are Y rated as well! http://www.falkentire.com/fk452_sizes.html
Nate, Great info bro appreciate it.............................................:cheers:elvicsmilieys::thumb3::rock::book:
That is good to know... We could maybe use this thread as a reference tool for correctly rated tires. I think we should stick to "Y" and "(Y)" rated tires. Why....... Our delima in these forums: To "meet or exceed' SRT8 performance standards, is a mimimum requirements issue to most members We really only desire to "EXCEED" standards. Which is very hard to do.. Therefore we have to make sure we buy top rated engine components, suspension systems, brake pads and kits, and rear axles. Since we will rarely be doing high speeed runs, we should make sure we know the tires required to at least meet or exceed SRT8 standards also. We may not all be road racing but if I happen to be seeing if my car will do 190"ish" on a long safe road, I want to know the only thing holding my car to the road at that speed is "feeling comfortable not stressed" .....And not being rapidly destroyed internally or externally, so that I get some rude failure or vibration of a tire during the high speed run or on the way home. (Remember... no spare... even IF you are able to stop safely from when you loose a tire). And blah, blah, blah... I think we should stick to "Y" and "(Y)" rated tires.
Nathan, can you follow up with the wear ratings? My understanding (ancient) is that they are not so well defined as speed ratings. It's much more a relative thing and more within the context of a company. So European wear ratings might not closely correlate with US wear ratings and even between companies. So if a Goodyear has a wear rating of 220 then you can expect more tread life out of a Goodyear with a wear rating of 440. I'm not sure if you could expect twice the tread life? On the other hand a Goodyear with a 220 wear rating might wear faster or slower than a Bridgestone with a wear rating of 220. How much this variance might be I don't know. Or are things a bit more in line now a days?
Wear ratings definately play #2 on the list... Lower number usually means shorter life but better grip. Higher number usually means longer life but less grip. I think tread design could effect grip but not life under normal driving. I will dig up some wear numbers on the tires mentioned here. All numbers based on 20" tire in 245 to 275+ widths and 35-45 height. 1) Falken FK-452: "Y" Rated / ? Wear 2) Goodyear F1 Supercar: "Y" Rated / 220 Wear 3) Goodyear RS-A: "V" or "Y" rated depending on size! / 260 Wear 4) Nitto Invo: "W" or "Y" rated depending on size! / 220 Wear 5) Pirelli P Zero: "Y" rated / 220 Wear 6) Vredestein Ultrac Sessanta: "Y" Rated / 280 Wear 7) Vredestein Ultrac SUV Sessant:a "Y" Rated / 280 Wear
Well, yea. I was wondering if you had anything handy pertaining to the wear rating system itself. Like I'm not sure if those numbers correlate to anything. So if you take 440 for example. Is there some rough mileage number you might expect? Or does it just mean that it will wear longer than a 220 from the same company. and how much longer than the 220.
You asked for it.... "UTQG Treadwear Grades are based on actual road use in which the test tire is run in a vehicle convoy along with standardized Course Monitoring Tires. The vehicle repeatedly runs a prescribed 400-mile test loop in West Texas for a total of 7,200 miles. The vehicle can have its alignment set, air pressure checked and tires rotated every 800 miles. The test tire's and the Monitoring Tire's wear are measured during and at the conclusion of the test. The tire manufacturers then assign a Treadwear Grade based on the observed wear rates. The Course Monitoring Tire is assigned a grade and the test tire receives a grade indicating its relative treadwear. A grade of 100 would indicate that the tire tread would last as long as the test tire, 200 would indicate the tread would last twice as long, 300 would indicate three times as long, etc." You can read more here at the Tire Rack (tirerack.com). Very good information in one place. "Tire Tech/General Tire Info" If you look at the top of the page you will see a drop down that gives you tons of technical notes relating to tires and tire use. Treadwear and Traction Grading info:http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=48 Speed Rating and Load Index info:http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=35¤tpage=55
Well, at least it looks like somebody is sort of overseeing it a little bit now. I wonder what they're using for the "course monitoring" tire? Must be made of used chewing gum. They're saying a wear rating of 100 would be the same as the monitor tire and 200 would be twice as long... I'm not sure I've ever seen a street tire with a wear rating of less than 200.
Just so those interested in Staggered RSA's know,the 295/40/20 is only H rated.Thats 130mph.So if you intend to do some high speed runs I'd look into a different tire.
damn nathan, spend a little time on the tire sites maybe???? hahahaha great info to have!!! sticky info for sure!!!!
Look at wear ratings this way: Imagine two distinct markets: An economy market, and a performance market. In the economy market, the incentive is for a manufacturer to give the highest wear rating possible, so expect a bias toward higher numbers, indicating longer tread life. Now in the performance market, the real enthusiasts know that the stickier the tire, the lower the treadwear rating. So it's fair to assume that a manufacturer will put the lowest number possible on the tire. In fact, in SCCA racing, there's different classes based on the treadwear rating of your tire. On tirerack, if you search for race tires, you'll note that treadwear ratings from 60-100 are the norm. Most "track" tires that are technically "street" legal, have a rating of 60. So if you're looking for performance, and the tire is rated at 300, you can assume you're not looking at a true performance tire. That being said, most of the best available SRT-8 tires have wear ratings of about 200.
just checked my nitto 420's...... speed rating - V (149mph) tread ware - 420 (longer life/less sticky) overall i like the tire, quiet, smooth, and aggrssive looking. wish it was slightly higher in the speed rating, but i RARELY ever see this level of speed.
Nice thread. I would ask this in a simple, straightforward manner: What would be the longest lasting tire with the best grip I should get for the BigBad Bitch (My Magnum, of course)?? Im hitting 8000 miles (I doint drive her that much, okay?) and the front tires are starting to show some marked wear. Rears seem okay though.
Longest wearing? Best grip? Those are mutually exclusive. There's an inverse relationship. The longer the wear, the less the grip. Shorter lifetime - more grip. You really need to decide where (wear?) on the spectrum you'd like to be.
Lets see,A good all around tire That hooks like a beotch off the line,High speed rating,High mileage,Great performing tire that is cheep.I been looking for that,Along with many other peeps for years.And believe me i am old.Maybe i am wrong but,i do not think it will happen any time soon.The majority of consumers want high mileage,And could care less how they perform.Just my .02
