Tire Speed Ratings

<div class='quotetop'>QUOTE(ekpolk @ Aug 14 2006, 07:14 PM) [snapback]303299[/snapback]</div>

:lol: LOL Sooo true!

Bob and fang,
Of course we sound ridiculous... we are. We're all wasting time here on a message board devoted to a particular type of car! But the 'game' is mileage, just like if we were talking sports cars the game would be speed/handling, or boom cars it would be SPL, etc.

I don't think anyone here is saying that a higher speed rating will always increase mpg. The question is if some higher speed rated tires might - due to stiffer sidewalls, and less tread deformation - acutally have low(ish) rolling resistance too. Kind of a happy accident.

I've done some racing over the years: cars, motorcycles, mountain bikes, and sailboats. With the most powerful machine (the car) we didn't worry much about tires. With the least powerful - my legs - tire rolling resistance/air pressure was a major concern. And not just for me - there's a massive ongoing discussion about bike tires. Ditto with the boat. Obviously it didn't have tires, but we fiddled with the smallest things - stuff that would make non-racers laugh their a$$es off, but that was the game.

 

<div class='quotetop'>QUOTE(efusco @ Aug 16 2006, 10:36 AM) [snapback]304174[/snapback]</div>

1) That's funny, I just aped his typo (and made it mine).

2) Yeah, that's it alright.

 

There is a difference polk. Me taking meds? Kind of you to say.

Yes it is ridiculous for those, that feel they have nothing to bring to the table except that they are that bored, they need to spell check the internet

Now as for dragracing, a tire selection will drop a hell of alot more than 1 tenth. This is a sport where the faster car/driver wins. I do things to my cars to make them faster to where it makes the reward and outcome worth while. We use what has been proven by thousands to make a car fast, not scratching and clawing wondering if something will get me 1 mpg more. Honestly, thinking about a higher performance rated tire to improve MPG isn't taking a step forward.

I want one person to name 1 tire manufacturer whose V, W, Y or ZR rated tire has gotten them more MPG compared to their H,S, and T rated tire of the same brand and model. In case you havent figured it out, the higher the rating on a tire, usually the faster the car it goes on and its intended purpose, which isnt fuel economy!

 

OK then, so how bout those METS...........

 

Hi Ek...,

It seems you are looking for some way to judge which tire will have less rolling resistance, when comparing tires that direct rolling resistance coeficient measurements are available. What little web research I did, I found that the LRR tires have high silica in the ware layers, besides the sidewalls that generate less heat when flexed, and higher inflation ratings to minimise the flex. Also, I found that the tire sizes dramatically effect the LRR coeficient, not just patch size but rim size and outside diameter too. So, if you cannot find a comaparison between the exact size tires in two different brands/models, the comparison wont be valid.

I had a scary slide in wet weather on the Integrities. So, I wanted something else, and before I used up too much trade in value. Did not hurt that the tire place has a $50 rebate on four tires the month I got them.

Looking around, I found that the Michelin Hydroedges used silica for better wet weather traction. And posts on PC here indicate nominal mileage reduction with them. So, I got those. After almost 2K miles on them, the mileage is back up to 1 mpg less than it was before, even using the AC on the drive home in 85 degree weather. I also put these on my old car, and it was like night and day with respect to road holding (OEM Firestones - yuck!).

I did not just go out and buy what I had good luck with previously. I bought them because they probably were going to have some LRR performance, but also allot better road holding, especially in the wet.

A high speed tire with a long wair rating, and silica content in the tread rubber might be the thing to look for to get LRR, if you cannot get the LRR data on the exact sizes you want to compare on the exact tires you are looking for, these three points might be a guide.

 

<div class='quotetop'>QUOTE(ekpolk @ Aug 16 2006, 10:17 PM) [snapback]304435[/snapback]</div>

Racing tires are about grip not roll resistance Did I speel that right DOC?! Speed rated tires don't necessarily have stiffer sidewalls. Michelin MXV4's are on our Cadillac performance models and not stiff what so ever. The biggest contributing factor for roll resistance in same sized tires is tread pattern followed by compound. Not speed ratings Not sidewall wall stiffness. Nuff said everyone kiss and make up now.

 

<div class='quotetop'>QUOTE(efusco @ Aug 16 2006, 08:36 PM) [snapback]304420[/snapback]</div>

Again, I didnt miss point 2. There just wasnt a point 2 that wasnt as pointless as being the spell checker for this site.

ROFL. There is a huge difference in what you wrote of 1/10 comment. Gaining 1 tenthoff an ET(do you know what that means?) is about the same as gaining 1 mpg. A simple tire selection will and can drop as much as 3-5 tenths off the ET. That is like gaining 10+ mpg. Big improvement I would say. I am not stupid, just the fact what you guys are trying to accomplish for that 1 MPG isnt progress. It looks to be out of desperation.

Like I stated before, some of you are going too the extreme of trying to gain maybe 1 mpg for the added cost of a higher perormance rated tire that wont improve your 45+ MPG. Kind of like you have done everything to improve MPG and now scratching and clawing at anything to gain whatever you gain because you can't.

:lol: :lol: I like that thinking.
So if I take all the gains and hp increases from the 1,000,000 of other dragracers, will I BE faster in the 1/4 mile? Give me a break. I work for Toyota, so I am familiar with how many Prius are on the road(even though I dont work in sales).

Personally I think you should ride a bike or take public transportation if 40+ mpg isnt good enough for you to where you need to look at a tires ratings and examine how it flexes under load and handling to see how much that will cause you to drop MPG.
LOL, I get 45% of what you guys get and have to use 93 octane and I can accept the fact I pay $100 a week in gas. Not to mention not a single customer of ours have complained of their MPG. That is why I cant believe many on here are spending more money to just to get a little bit more in MPG.

BTW treadware ratings are useless unless they are being compared on the same brand of tires only.

If you all think you all piss me off, sorry I deal with people all dayand some rude ones that feel they should get their cars worked on for free. You need to do better than this to piss me off.

 

I agree, Fang you need to lighten up . I come from a racing background as well ( '87 vortech blown 351 Mustang GT, '00 C5, '00 T/A heads/cam/nitrous 4400stall, '90 454SS P/U etc) and I see no difference in trying to maximize MPG than in trying to maximize ET or MPH or 60' or whatever. Its all the same. Slamming someone because they have a unique thought that may spur forward thinking is about as backwards thinking as you can get.

 

I am a drag racer as well, however I compete in bracket races which requires absolute consistency to be successful. A tire is nothing more than the final component of a suspension system and it must work in conjunction with all other suspansion aspects in order to provide the maximum benefit to the task. The same rules apply to duel economy and all the "little things" add up to often make a significant difference.

most people think i am a nutcase with my weather station, record books, computer, and all the other trappings of a bracket racer but the proof is in the pudding. If enough attention is paid to detail, and if the driver it attentive enough, and if the guy in the other lane doesn't have a "perfect run" then there are many ways to win and lose in racing.

That same attentian to detail and science as applied to miles per gallon will help all of us hopefully save a buck or two at the tank as well as preserve our finite fossil fuel resources and maybe even help keep the environment a bit cleaner for the next generation.

I see no reason performance rated tires should be excluded from research, but I also would not expect much return on the effort as their primary purpose is usually directed at performing a few tasks extremely well and sometimes at the expense of others.

Additionally the development costs of high performance tires and testing and their often shorter lifespan may actually consume more fuel on the back end than it might save on the front end so despite the possibility of saving at the pump there may be a net loss from an overall consumption perspective.

In general, i think it better to exclude performance tires from the various ratings as they have a limited buyer demographic and usually serve specialized needs as opposed to being a broad base product.

 

If you're seriously searching for information about rolling resistance and fuel consumption of different tires, look at the excellent, thorough, scientific study done by the Transportation Research Board of the National Academies. It was published this July here.

Here's an excerpt on the observed rolling resistance of different speed ratings.

Here's an overview of the primary source of rolling resistance.

 

<div class='quotetop'>QUOTE(ekpolk @ Aug 18 2006, 12:09 PM) [snapback]305356[/snapback]</div>

When choosing specific tires, be sure to reference the raw data for the report. The National Academies' Transportation Research Board has published energy and performance characteristics of the nearly 200 passenger tires examined in the report.

If I lived in Florida and didn't have to worry about snow or ice traction, I'd buy the low rolling resistance, low cost, Sumitomo HTR 200 high performance summer tire. According to the report data, it offers lower rolling resistance than the Integrity. According to the Tire Rack, it offers MUCH better traction, handling, and safety on dry and wet roads. I'd choose size 205/60HR15 for traction and improved speedometer accuracy or size 195/60HR15 for fuel efficiency.

 

<div class='quotetop'>QUOTE(efusco @ Aug 18 2006, 01:39 PM) [snapback]305427[/snapback]</div>

... and my LRR favorites:
ContiProContact < ContiTouring Contact CH95 = 0.00825
Sumitomo HTR 200 = 0.00923

(Continental has replaced the ContiTouring Contact CH95 tires with the ContiProContact, which they claim offers delivers even lower rolling resistance. The Ecos or Greenseal data used in the report indicate that the CH95 has a rolling resistance coefficient of 0.00825)