Veloce Raptor

FYI, this doesn't do beans except scrape the gravel off your tires. The way to warm them is to accelerate & brake, accelerate & brake. This puts heat in them.

ProCoach

^^This^^

The fabric and metal belts under the tread in the carcass of the tire are laid on an angle to each other from bead to bead. The acceleration and braking cause the belts to shift in relation to each other, generating heat from the inside out. This raises tire pressure efficiently and quickly as well as heating the tread surface.

ervtx

Not to mention the value in checking out your brakes and pedal travel before heading out!

pontifex4

And making sure no one tailgates you!

sig_a

In my case, switching from new 15" Pirelli 6000's (UTQG 400) street tires to 17" Nitto NT01's (100 UTQG) on my 5th DE day at Mid Ohio (green group) was both smart and safe. 2011 season, I used Kumho v710's (UTQG 30), which are surprisingly good on a wet track.

The thing to focus on when evaluating is the current street UTQG or tread hardness vs. something considerably softer at UTQG 100 or 60 or 30. What others at your level of experience are using is a very helpful guide.

The term R Compound gets tossed around a lot. I'd like to know what an accurate definition consists of.

stownsen914

The OP has done a bunch of track days, so he could be ready for sticky tires. But it depends on how fast the driver is, and how close to the limit he's able to drive. I think many drivers make the switch to R compound tires too soon. It's hard to learn how to safely drive at the limit. It's harder when you increase the limit. This can be complicated by the fact that with some race tires the limit is harder to detect. If you switch to R comps too soon, you make go a little faster in the near term, but impede your learning. This can result in being a slower driver down the road a ways, compared to one who takes the time (on street tires) to learn WELL how to handle a car near the limit.

Scott

Doug007

R-comps are DOT approved tires vs. slicks which are not. In general the treadwear rating is less than 100 to be called a r-compound tire.

Tire / Treadwear
Star Spec / 200
Yoko AD08 / 180
RE-11 / 180
Kumho Ecsta XS / 180
Hankook Ventus R-S3 / 140
RA-1 / 100
R888 / 100
NT01 / 100
Hoosier R6 / 40

Veloce Raptor

Yup!


IIRC, the treadwear rating is a relative number only with other tires by the SAME manufacturer, and can't really be used to cpmpare tires from different manufacturers. I could be wrong--anybody know this??

Doug007

From tirerack.com

"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.

The problem with UTQG Treadwear Grades is that they are open to some interpretation on the part of the tire manufacturer because they are assigned after the tire has only experienced a little treadwear as it runs the 7,200 miles. This means that the tire manufacturers need to extrapolate their raw wear data when they are assigning Treadwear Grades, and that their grades can to some extent reflect how conservative or optimistic their marketing department is. Typically, comparing the Treadwear Grades of tire lines within a single brand is somewhat helpful, while attempting to compare the grades between different brands is not as helpful."

Veloce Raptor

So each manufacturer sets the rating. That's pretty much what I figured--it's all relative to their other tires, which is why I usually ignore it.

utkinpol

here is a couple of good generic links, but they do not cover all the choices.
http://www.racingtireguide.com/autoc...eet-tires.html
http://www.autocross.us/forums/index.php?showtopic=5084

rennlist`s current consensus on 'streetable' r-comps pretty much narrows down to NT01 tires only. with R888 toyos as only other candidate.

if you can tow your car - get into R6 hoosiers.

PS. Z1 star specs are way softer than RE11 or ecsta tires. '200' rating is BS. R-S3 are made from r-comp compound and their '140' is another BS so they can be used in 'stock' and 'street' classes. would be a great tire to use if they would make more usable sizes.

Doug007

+1

As long as the OP is getting 15 track days from "street tires" I see no need to switch to r-comps for DEs.

multi21

The OP is overdue for r comps with 30 days on track and modified suspension.

Matching the right tire to a track car is extremely complicated depending on what level suspension you have and brake mods if any.

My suggestion would be to start with a good r comp tire that you can use in the rain if needed and drive to and from the track. My first choice is the NT01 and then the Toyo RA1. The Toyo 888 are crap. Michelin sport cups are over priced and heat cycle out.

In addition, a set of NTO1 is very close to or less than a set of very good street tires.

You'll see a difference, not only in corning loads as others have suggested here, but your braking distances will be shorter and you'll be able to get on the throttle much sooner.

Hoosiers are an entirely different story. The first time you mount those up, you'll think they put stiffer springs in your car because the sidewalls are so much more stiff than a street tire or the aforementioned NTO1 or RA1.

Once you go into Hoohoos, the money starts flying out the window..... But thanks for contributing to the economy!

dan212

Another factor - It kind of depends on how you are getting your car to the track. If by trailer, you can use R-Comps like MPSC or the like. But if you plan on driving home on them I'd think twice. I have fun with MPSC's in the rain. But not on the highway.

Leica356

Get a second set of wheels. Look at the Hankook Z214! I went to rcomps after 8 or so trackdays. A little early but it's so much fun, which is the point! They can hide bad habits which you shouldn't have with that much track time.