Tire points

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Tire points

Postby Greg Phillips on Wed Feb 09, 2011 4:58 pm

OK, we have had about enough fun discussing weighty issues.
Time for a new topic of discussion, proper penalty points for tires 8)
The concept for penalty points is that the penalty points should be in proportion to the increase in performance provided. Tires have been under valued for years in our old system.
It did not cause a lot of problems because once you moved out of street stock class, you needed to use R rubber to be competitive and everyone in S, P,I, M, or R was running them.
But in the new system, except for street stock, there will now be overlap of cars that may be running street or R tires. A stock Boxster on street tires may be in the same class as a GP 944 on R tires. If the tire points are not adequate, it will be unlikely anyone could win without using them. That is the wrong approach, so I propose they be more fairly penalized. :rockon:

Under our old system, we only had 4 different groups for R tires.
DOT tires > 139 are 0 points
DOT tires 50 to 139 are 2 points
DOT tires 0-49 are 4 points
Slicks (non DOT) tires are 6 points
In the new system (x10) they are now 20, 40 or 60 points.

In the GGR system, tires were handled differently:
a)Tires with DOT wear rating 200 or greater= 0
b)Tires with DOT wear rating less than 200 but greater than 100 =25
c)Tires with DOT wear rating less than 101 but greater than 49=50
d)Tires with DOT wear rating less than 50= 100
e)Racing slicks or tires with no DOT wear rating=175

I would propose a change somewhere between these.
Soft compound high performance tires (DOT Street legal) with a DOT tread wear rating of 140-199 : 20 points
DOT tread wear rating of 50-139 : 40 points
DOT tread wear rating of 1 – 49 : 80 points
(Any tire with a 0 (zero) DOT rating is considered a race tire and subject to rule C.).
C. Tires with a 0 (zero) DOT treadwear rating - 120 points
Race tires or slicks, defined as non-DOT tires - 160 points

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Re: Tire points

Postby Cajundaddy on Wed Feb 09, 2011 6:36 pm

+1
In past years the performance/penalty re tires was large. If you wanted to seriously compete beyond street stock that meant running really soft rubber and a really big tire $$ budget. Bringing relative performance/penalty into line removes the huge incentive to spend $1K on tires for a weekend TT. You can still always run soft rubber but it will be relative in points to other car mod choices.
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Re: Tire points

Postby Steve Grosekemper on Wed Feb 09, 2011 8:16 pm

+1
I think the tire penalty issue is at the heart of what is wrong with the old/new system. No one can argue tires are not the easiest way to go way faster. The points penalty should reflect the performance advantage.
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Re: Tire points

Postby Gary Burch on Thu Feb 10, 2011 7:24 am

+1

I fought this battle a few years ago, maybe now is the time to actually do something about tire points.
Tires have the single most impact on lap times and should be valued that way.
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Re: Tire points

Postby Mmagus on Thu Feb 10, 2011 8:38 am

Yes, yes, yes, yes...and yes. (Did I agree with the right number of posts? :roflmao: )

I am currently at 290 points, CC15 Class. Given the system as it is if I had the funds and inclination I could:

a. Go to a 205 racing slick tire and still stay in class.
b. Add camber plates AND slicks in my current size tire and only move up one class.

Either of these options would, IMHO, be rediculously hard to beat. Well...unless Jad, Grosekemper, or Eric drop to CC15/CC14 then, it woldnt matter WHAT I ran. :beerchug:
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Re: Tire points

Postby Jad on Thu Feb 10, 2011 9:27 am

Am I forgetting something, what tire has a dot of 1-49? I can think of 0's and 50's, but not anything in between?

I guess I might vote for simply doubling the current penalty, so 40, 80, 120. The dot thing is pretty arbitrary so too many categories seems excessive. To me, there are street tires, 0 points, dual use R compounds 40 points, normal race tires 80 points and full slicks for 120 points. Clearly not a perfect solution, but remember, most people running 'good' tires are not running stickers every time and you probably don't want to overshoot points by so much that you can't compete if you have race tires? Their advantage is quickly reduced significantly with a couple heat cycles. Just an added issue to consider, sorry.
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Re: Tire points

Postby rshon on Thu Feb 10, 2011 9:35 am

Jad wrote:Am I forgetting something, what tire has a dot of 1-49? I can think of 0's and 50's, but not anything in between?


Hoosier A6/R6, Kumho V710, BFG R1, Hankook Z214 (mostly 40 except for the V710, which is 30)...
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Re: Tire points

Postby ttweed on Thu Feb 10, 2011 10:02 am

Steve Grosekemper wrote: The points penalty should reflect the performance advantage.

This is the ideal, undoubtedly, but I'm not sure the proposed scale of penalties reflects this accurately.
Greg Phillips wrote:Soft compound high performance tires (DOT Street legal) with a DOT tread wear rating of 140-199 : 20 points
DOT tread wear rating of 50-139 : 40 points
DOT tread wear rating of 1 – 49 : 80 points
(Any tire with a 0 (zero) DOT rating is considered a race tire and subject to rule C.).
C. Tires with a 0 (zero) DOT treadwear rating - 120 points
Race tires or slicks, defined as non-DOT tires - 160 points

My thoughts:
1. There are a number of 200-240 treadwear tires that are very capable, yet they would receive no penalty under this rule, though they are much faster than a standard 300-400 treadwear street tire, and take less of a performance hit from heat-cycling than a DOT-R tire over their life. An excellent example is the Falken RT615K @ 200 UTQG. If this rule went into effect, that's the first place I'd go, and drop 1-1/2 classes in my car. Are we simply trying to encourage the use of street tires in the CC classes?

2. Are there actually road racing tires with a 0 UTQG rating that are DOT legal? The only ones I know about are drag-race radials. Is anyone using them? Have they proven to be so effective in lowering lap times that they deserve 40 more points than a Hoosier A6/R6 (UTQG 40) or V710 Kumho (UTQG 30)? Examples or data on this difference would be helpful--I'm simply not aware of this class of tire being such an advantage in our autox/TT applications. Why is it not mentioned in the GGR rules, or our previous rule sets? Have I overlooked the development of a new killer tire somehow?

3. Just as the development of street tires has resulted in 200 treadwear tires that grip like the R-compounds of old, the development of < 50 UTQG-rated DOT-R radials over the years has nearly approached the grip of full race slicks now. The compounds are similar, the only difference being a couple of small tread grooves and a slightly more robust construction for the DOT-R tires that adds a little unsprung weight compared to full race slicks. I don't think the difference in performance equates to twice the penalty points (80 vs.160). I would guess the differential to be more like 20 points, as it is in the existing rules.

In general, I think a more than 3-class bump (160 points) is far too great a spread between the slowest and fastest performance tires, and don't believe there is a big enough performance difference to justify it, considering how fast R-compounds heat-cycle out, and compared to our other penalties. For 160 points, you can add 160 mm of width to your tires, increase your engine displacement by 44%, increase your horsepower by 352, or decrease weight by 400 lbs. Are these all really equivalent improvements to adding a set of slicks vs. a 200 treadwear performance street tire?

The new rule set for 2012 already includes an increase of 50% in the penalties for <50 UTQG rated tires and 25% for race slicks over our existing 2011 (and previous) rules:
DOT tread wear rating of 140-199 = 20
DOT tread wear rating of 50-139 = 40
DOT tread wear rating of 49 or less = 60
Race tires or slicks, defined as non-DOT street legal tires = 80

This new proposal doubles that increase. Why not give the new rule a chance before increasing the penalty further?

TT
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Re: Tire points

Postby gulf911 on Thu Feb 10, 2011 10:35 am

"In general, I think a more than 3-class bump (160 points) is far too great a spread between the slowest and fastest performance tires, and don't believe there is a big enough performance difference to justify it, considering how fast R-compounds heat-cycle out, and compared to our other penalties."

+1 Tom!
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Re: Tire points

Postby Jad on Thu Feb 10, 2011 10:37 am

rshon wrote:
Jad wrote:Am I forgetting something, what tire has a dot of 1-49? I can think of 0's and 50's, but not anything in between?


Hoosier A6/R6, Kumho V710, BFG R1, Hankook Z214 (mostly 40 except for the V710, which is 30)...


Sorry, looking at several site, the Hoosiers/Kumho's always say DOT legal, don't use on street. I thought that meant they were DOT approved, but rated 0 as the street tires always said DOT XXX. My bad, thanks.
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Re: Tire points

Postby Greg Phillips on Thu Feb 10, 2011 11:50 am

Jad wrote:
rshon wrote:
Jad wrote:Am I forgetting something, what tire has a dot of 1-49? I can think of 0's and 50's, but not anything in between?


Hoosier A6/R6, Kumho V710, BFG R1, Hankook Z214 (mostly 40 except for the V710, which is 30)...


Sorry, looking at several site, the Hoosiers/Kumho's always say DOT legal, don't use on street. I thought that meant they were DOT approved, but rated 0 as the street tires always said DOT XXX. My bad, thanks.

The 0 treadwear may be a carryover rule as it seems the common R tires have a treadwear rating 30-100.
The Hoosiers when they first came out apparently did have a 0 treadwear rating.

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Re: Tire points

Postby Kim Crosser on Thu Feb 10, 2011 12:35 pm

A 0 tread wear rating is an interesting concept. Wouldn't that have the life expectancy of a soap bubble? :wink:
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Re: Tire points

Postby Mmagus on Thu Feb 10, 2011 12:51 pm

Kim Crosser wrote:A 0 tread wear rating is an interesting concept. Wouldn't that have the life expectancy of a soap bubble? :wink:


After seeing the results of ONE tough spin by Paul on his NEW Hooziers...flat spoted through the tred line. :shock: Soap Bubble seems about right.
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Re: Tire points

Postby Otto on Thu Feb 10, 2011 1:39 pm

Tom Tweed wrote:

quote

In general, I think a more than 3-class bump (160 points) is far too great a spread between the slowest and fastest performance tires, and don't believe there is a big enough performance difference to justify it, considering how fast R-compounds heat-cycle out, and compared to our other penalties. For 160 points, you can add 160 mm of width to your tires, increase your engine displacement by 44%, increase your horsepower by 352, or decrease weight by 400 lbs. Are these all really equivalent improvements to adding a set of slicks vs. a 200 treadwear performance street tire?

The new rule set for 2012 already includes an increase of 50% in the penalties for <50 UTQG rated tires and 25% for race slicks over our existing 2011 (and previous) rules:
DOT tread wear rating of 140-199 = 20
DOT tread wear rating of 50-139 = 40
DOT tread wear rating of 49 or less = 60
Race tires or slicks, defined as non-DOT street legal tires = 80

This new proposal doubles that increase. Why not give the new rule a chance before increasing the penalty further?

Tom Tweed -- #908

unquote

I fully agree with you Tom.
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Re: Tire points

Postby rshon on Fri Feb 11, 2011 2:17 am

ttweed wrote:For 160 points, you can ... increase your horsepower by 352...


Tom, I don't think that's quite right. Under the new rules, a 72 hp gain is 160 points. A 352 hp increase would be 774 points...
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