is there are list of the "street" r compounds?

[blowne34]

like the azenis are r comps but there classifieded as street.
is there a list or a tread rating?
thanks

[sab0276]

Basically you are looking for what TireRack calls an Extreme Performance Summer Tire. These tires usually sacrifice wet traction and tread wear for outright dry grip.

Here are the best of the best:
Dunlop Direzza Z1 Star Spec 200TW
Hankook R-S2 200TW
Hankook R-S3 140TW
Bridgestone RE-11 180TW
Yokohama AD07 180TW
Yokohama AD08 180TW
Kumho XS 180TW
Nitto NT05 200TW
Falken Azenis 200TW
Toyo R1R 140TW

All will perform fairly closely in the dry, even the really inexpensive ones (Hankook, XS, NT05, Azenis, etc). If you want every last hundredth of a second, you'll need to pony up for the higher priced ones (Yokohama and Bridgestones). Some are good in the wet, others not so much.

To be legal for street class they must be 140 TreadWear. You'll want to look for 140-220TW tires. I don't think there are any tires above 220TW that are worth looking at if want to be competative. You'll be compromising traction for tread wear, noise, etc.

-Scott

[edw1]

SCCA requires a treadwear rating of 140 or higher in their street tire classes. 24 Hours of LeMons requires 200 or higher.

[sab0276]

Good point Ed. I think BMWCCA autox rules also classifies 140TW tires as street.

-Scott

[edw1]

Good point Ed. I think BMWCCA autox rules also classifies 140TW tires as street.

-Scott

Yes, we currently mimic SCCA rules so 140 and higher is "street" and <140 is "race" adding 15 points to the modifications. We have occasionally discussed adding an "intermediate" class inbetween adding less than 15pts.

[ivan]

Oh no... the dreaded 'cheater tires should be punished' topic. Run!!!!

We have occasionally discussed adding an "intermediate" class inbetween adding less than 15pts.

If we do that, then some will ask for a stepped approach for r-comps (rightly so). The time difference between a decent max performance and ultra performance "cheater" streat tire is about the same as the time difference between the budget r-comp (ra1, r888, nt-01) and the V710/A6.

Then somone needs to sit around and drop each tire into 4 different buckets. And get flogged for getting the bucket "wrong". Slippery slope...

Gotta pay to play with the big boys! (says the driver of a tin can on wheels to another driver of a tin can on wheels )

[Timmah]

Well, I don't know about all that AutoX classification jibber-jabber, but I love me my Dunlop Direzza Z1 Star Specs! They are even fine in the rain!

[dngo]

This is where I usually step in and say:

Buy 710s!!

To add to what everyone has said, the Azenis is not a R comp tire. It really is a street tire, albeit one that is not great in the rain and will wear quickly. It is pretty much equivalent in grip to a lower performing R comp like a Yokohama A032R when it comes to autox.

Dave

[ivan]

Yes, the Azenis is basically old news... they are still really good for the money, but the newer generation tires match/beat it in the dry and are WAY better in the wet and to daily drive on. The only exception is the Kumho XS - no good in the rain.

[jnscaldwell]

I have the Bridgestone RE-11s and use them as a rain tire for the track. I have run them in the dry and they have tons of grip. They give a lot of feedback and plenty of warning when ready to break loose. I would highly recommend these, probably would be great for autocross. The wear is unbelievable and after maybe 8 days in the dry on the track they show negligible wear. Well worth the $$$ IMHO.

[staianoa]

Keep in mind that Bridgestone RE50A's are stock on nearly every BMW with a sport package these days and comes with a treadwear rating of 140. Yes they wear out extremely quickly and deliver great grip, but are they really equivalent to R Comps?! I think that as tire technology increases it becomes much more difficult to assess points in big lumps for race tires or street tires. That said, I certainly wouldn't want to have to classify each tire. Perhaps a sliding scale based on tread wear rating or speed rating would be most suitable. In the mean time... I'm going to continue to enjoy the sticky street tires!!

[ivan]

Perhaps a sliding scale based on tread wear rating or speed rating would be most suitable.

Tread wear ratings are usually subjective and don't always correlate to the tire's actual real world performance. For example, the RE-11 rated at 180. The RE050 are rated at 140. Yet the RE-11 is a faster track and autox tire.

I say just leave it as is.

[edw1]

Here is a simple formula for equalizing tires under a 200 rating.



TR = Treadwear rating

Base tire points (BP) = 1pt * (200-TR)/10

Tire manufacturer modifier (TM) is 1 unless specifically mentioned below
Hoosier = 1.4
BFG = 1.2
Kumho = 1.2

Driver modifier (DR) is 1 unless your name is below
Dave = 1.5
Ivan = 1.25
Ken = 0.9
Brent = 0.75

Drivetrain modifier (DT)
RWD = 1.1
FWD = 0.95
AWD = 1

Model/chassis modifier (MM) = 1 unless mentioned below
M3 (any chassis) = 1.3
E30 (non-M3) = 0.95
E21 = 0.75
5 series = 0.75
7 series = 0.5

Carbon fiber component modifier (CF)
Carbon fiber components = 1.25
No carbon fiber components = 1

LeMons Modifier (LEM)
LeMons car = 0.8
non-LeMons car = 1

Tool modifier (TOOL)
Cordless impact gun = 1.2
No cordless impact gun = 1

Motorsport country club modifier (NJMP)
Membership in any Motorsport facility = 1.375
No membership = 1


Tire points = BP * TM * DR * DT * MM * CF * LEM * TOOL * NJMP

[ivan]

Tire points = BP * TM * DR * DT * MM * CF * LEM * TOOL * NJMP

LOL!
Man, I am glad I stopped changing tires and just run streets. No TOOL multiplier for me. Sucks for Dave.

[mmarv]

No TOOL multiplier for me.

No comment.