2016 tire rules for street stock

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Re: 2016 tire rules for street stock

Postby Greg Phillips on Mon Feb 01, 2016 10:12 pm

jbrennen wrote:
Greg Phillips wrote:Again, if you are buying tires and wheels to autocross or go to the track, you should be running in a CC class IMHO


The SS rules should reflect the reality of car ownership, which is that tires are consumables and that most owners aren't particularly interested in doing the research to figure out what tire models were available for factory delivery on their car. They will buy the tire that gets good reviews, or the tire that's on sale, or the tire that's available for immediate delivery (rather than waiting two weeks on a back-ordered tire).

Once you accept the idea that car owners don't place any particular value on sticking with the factory tire model, and that replacing tires is not viewed as a "modification" by most people, you have a little bit of a problem enforcing your quoted sentence above... How do you determine if an owner bought tires "to autocross"? The guy who buys the Bridgestone RE-71R because he read about it on an autocross forum is sent to CC class, but the guy who bought the same tire because it had the highest dry traction rating on Tire Rack's website gets to run SS? (It does have the highest dry traction rating there, by the way...)


You don't have to tell me that tires are a consumable and all the reasons you could buy different tires :surr: I go through a lot of them and always looking for deals :rockon:
I was not trying to have a rule about why you were buying different tires, only evoking the spirit of Street Stock.

But here is another thought that Steve Grosekemper mentioned as an option for Street Stock.
Each of the cars would be placed in their respective Street Stock categories based on their base points, tire size and any allowed performance points (ie factory options like PDK or limited slip). Modifications would be limited as they are now, but hopefully you would be competing against a car of more equal performance.
An example would be my 2005 987 Boxster. It is bone stock with 205 front and 255 rear tires. It presently would run in SS02 or with 409 points (359 base + 50 tire points) in CC05.
Under a new proposal, each SS class would encompass cars with a certain number of points, and they could move up or down depending on tire size and any added ALLOWED performance options.
If I increased my tires to 265 and 235, I would take 40 points and if I had PDK another 15 points. Depending on where you were in your SS class you may have to move up a class.
The main difference between CC and SS then would be that SS would not allow all tires, only those with approved treadwear ratings and that performance modifications would be limited to factory options or as allowed (muffler delete, catback exhaust?).
No aftermarket suspensions or engine changes etc.
There would need to be some work to determine how many SS classes to allow and what each of their point ranges would be, but I think the concept has merit.
We already have a formula for the performance potential and modifications, we would now use it for SS cars for their limited allowed modifications.

Greg
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Re: 2016 tire rules for street stock

Postby jbrennen on Tue Feb 02, 2016 12:18 am

I guess my take on this is that whenever you have classing rules, there will be those competitors who build their car around the rules, and there will be those competitors who just show up and then find out what class they're in.

That first group is always going to have an advantage over the second group.

If that's perceived as a problem, there's a solution -- change the rules often. But personally, I don't want to go there -- I think there is value in allowing drivers to build a "best-in-class" car and to reap the rewards of that build. And yes, even in SS, building a best-in-class car requires doing your homework and opening your wallet. ;)
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Re: 2016 tire rules for street stock

Postby JayG on Tue Feb 02, 2016 9:21 am

I like what Greg is proposing. Having points adjust up or down what SS class you run in
Especially a PDK which IMHO give a huge advantage, keeping the car in the power/torque performance band at all speeds. A PDK will even downshift to 1st in an AX and I don't think those of us with a manual would do that.

Yes,I know that the driver makes a big difference, but 1-3 seconds in an AX between PDK cars and manual cars is a huge difference

We should look at this over the 1st half of the season and go from there. Perhaps at the PDS AX we could do some testing with a couple of cars PDK and manual with the same drivers driving both and see what the results are
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Re: 2016 tire rules for street stock

Postby Cajundaddy on Tue Feb 02, 2016 1:36 pm

There is always some angst and heartburn over specific rules that "seem" to make a big difference in the results... until we look at the actual results. I was one of those angst/heartburn guys once, and then I got drafted to sit on the Z8 rules committee. Be careful what you wish for. :idea:

Remember that there are no perfect rules. Every rule set, including PCA, SCCA, Grand Am, or F1 has limitations, quirks, shortcomings, and loopholes that enterprising drivers will always seek to exploit. The winningest drivers often work carefully within the existing rules rather than attempting to change them. See Top 10 results for examples. 8)

Looking forward to your thoughtful and carefully prepared rule proposals for next year. Now let's go driving! :beerchug:
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Re: 2016 tire rules for street stock

Postby JayG on Tue Feb 02, 2016 2:01 pm

Cajundaddy wrote:There is always some angst and heartburn over specific rules that "seem" to make a big difference in the results... until we look at the actual results. I was one of those angst/heartburn guys once, and then I got drafted to sit on the Z8 rules committee. Be careful what you wish for. :idea:

Remember that there are no perfect rules. Every rule set, including PCA, SCCA, Grand Am, or F1 has limitations, quirks, shortcomings, and loopholes that enterprising drivers will always seek to exploit. The winningest drivers often work carefully within the existing rules rather than attempting to change them. See Top 10 results for examples. 8)

Looking forward to your thoughtful and carefully prepared rule proposals for next year. Now let's go driving! :beerchug:



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Re: 2016 tire rules for street stock

Postby Witteried on Tue Feb 02, 2016 11:20 pm

An interesting observation from my experiences last season. Last year I changed my tires to less sticky rubber which dropped me from CC-04 (on tread 40) to CC-02 (tread 200). When I was in CC-04 I had tight competition with cars in that class, and when I went to CC-02 the competition was still tight. At one event all three CC-02 cars were within 0.1 seconds (‘69 911, ‘76 911, and a 944)! Some events I won, some I lost. I don’t understand why some are reluctant to move into CC at whatever spending level they want. You don't HAVE to do anything to the car to be competitive, contrary to what has been said above; the points system seems to level the competition pretty well. If you choose to optimize a car within a class, your upgrades (and cash spent) will be restricted unless you decide to move up a class or two.

I suggest figuring out your Porsches class in the CC structure, but continue competing in your current SS class and see how you would have done in CC this year if you had made the change. You might be surprised. Keep in mind that the nut behind the wheel is a major factor, not just car modifications. :D


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Re: 2016 tire rules for street stock

Postby ttweed on Wed Feb 03, 2016 7:39 am

Greg Phillips wrote: ...The main difference between CC and SS then would be that SS would not allow all tires, only those with approved treadwear ratings and that performance modifications would be limited to factory options or as allowed (muffler delete, catback exhaust?).

I'm not sure if I understand what you're saying here, Greg. Muffler delete and catback exhaust are not allowed mods currently in SS. Are you saying that under this new SS proposal there would be a widening of the allowable performance mods to include them?

As I understood the original intent for the inclusion of SS classifications in our ruleset, it was to allow members to prepare and practice in their cars to compete in the Parade autocross competition in the SS classes. If that was the actual intent, it seems to me that we should be making changes to conform with the changes in the PCRs that have taken place. We seem to be going in an entirely different direction, and I'm not sure why.

TT
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Re: 2016 tire rules for street stock

Postby Jad on Wed Feb 03, 2016 10:18 am

To me, the SS class is for people who just want to drive what they bought and drive every day. A small allowance was made as this 'daily driver' often has after market wheels and tires for looks. However, if you are 'building' a car to optimize it, run CC, leave SS for the regular cars. You can't make rules that prevent someone from having their engine rebuilt by a pro to 'stock', new sticker tires for timed runs and hundreds of pounds removed to meet the 'official' weight of their car. Also, NO ONE IS DOING this in SS, so don't waste energy trying.

I am not sure I understand the logic in having the SS classes as parade prep (though that may have been the original concept). It isn't like your car needs to practice in a certain class, just learn to drive whatever setup you will drive at parade. Labeling the class really won't affect your parade results. Of course, the number of SS drivers going to parade is rather small as far as I can tell, so why bother?

I have two cars, one is a car optimized for CC12 that I run at time trials, one is a cab on 6 year old tires (not optimized) that I run at Parade and an occasional AX. Both win their classes.

Have the CC classes for modified, optimized cars, SS for just arrive and drive cars. As said, the driver makes a much bigger difference than any 'options' added to the car. :surr:
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Re: 2016 tire rules for street stock

Postby jbrennen on Wed Feb 03, 2016 11:27 am

Jad wrote:To me, the SS class is for people who just want to drive what they bought and drive every day. A small allowance was made as this 'daily driver' often has after market wheels and tires for looks. However, if you are 'building' a car to optimize it, run CC, leave SS for the regular cars.


There's definitely a challenge to seeing how fast a car can be while still remaining basically "stock"...

Here's my "built" SS-legal car (981 Cayman GTS):

Factory configuration:
1) Base 2-way seats (for less weight)
2) PDK (faster shifts)
3) PTV (limited slip diff)
4) X73 (sports suspension)

Post-factory "build":
1) RE-71R tires (because the OEM Goodyear tires couldn't handle autoX on stadium lot -- I tried but they chunked badly); they are 10mm wider than stock (245/275 instead of 235/265) because at the time I ordered them, there was no 235/265 option
2) 19-inch OEM 987 wheels (because my car as a GTS could only be ordered with 20-inch wheels -- I never wanted 20-inch to begin with, 20-inch tires are too expensive and selection too limited)
3) Alignment (because the stock alignment is all wrong for autoX and would chew up the outside shoulders of the tires)

It's also a daily driver, with over 11,000 miles in less than 14 months of ownership. I run 91 octane gasoline, have made no weight reduction changes, and have never touched the engine except for one oil change. Brakes, including fluid, are as delivered from the dealer. Suspension is as delivered from the dealer, with just alignment changes.

So there's my build. I went down on wheel size to give me more choice of affordable tires, and I changed alignment and tires because the stock alignment and tires couldn't handle the demands of autoX.


The subject of the thread was about tire rules -- I can state that the RE-71R tires are several seconds faster than the OEM Goodyear tires on an autocross course. Don't get me wrong, I'm definitely using the right tire to go fast by SS rules. But it's not because of size -- the extra 10mm width is probably inconsequential. It's because of tire compound.

If you want to keep RE-71R tires out of SS, you could exclude them specifically. There was a lot of talk in the SCCA about doing exactly that for 2016 for their Street classes. They eventually decided that if you ask the tire manufacturers to make better autocross tires that are also usable for daily driving, you shouldn't panic when the tires show up and exceed your expectations. :)
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Re: 2016 tire rules for street stock

Postby Jad on Wed Feb 03, 2016 3:20 pm

To me, if you really do anything to the car with the intention of making it better at AX, you should graduate to CC. SS is for people showing up to drive in what the factory delivered or happens to be on the car. Nothing wrong with improving it for better times, but to me, that is now a CC car and there is a perfect class for just your mods. Optimizing a car for SS seems wrong to me, but totally appropriate to the rules.

Just my $.02.
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Re: 2016 tire rules for street stock

Postby mrondeau on Wed Feb 03, 2016 3:37 pm

Jad wrote:To me, if you really do anything to the car with the intention of making it better at AX, you should graduate to CC. SS is for people showing up to drive in what the factory delivered or happens to be on the car. Nothing wrong with improving it for better times, but to me, that is now a CC car and there is a perfect class for just your mods. Optimizing a car for SS seems wrong to me, but totally appropriate to the rules.

Just my $.02.


I don't see tire changes and alignment as a problem. I think that arguing about tire compounds or an extra 10mm of tire is silly and a good driver can overcome that. Drive the best tire you can. I run my street car in a CC class because of its age and a few small modifications that make it more enjoyable at the track. :wink: I do like the RE71R tires though. Even though they don't make the optimum size for my car, they're still ok. :roflmao:
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Re: 2016 tire rules for street stock

Postby Steve Grosekemper on Wed Feb 03, 2016 4:38 pm

ttweed wrote:
Greg Phillips wrote: ...The main difference between CC and SS then would be that SS would not allow all tires, only those with approved treadwear ratings and that performance modifications would be limited to factory options or as allowed (muffler delete, catback exhaust?).

I'm not sure if I understand what you're saying here, Greg. Muffler delete and catback exhaust are not allowed mods currently in SS. Are you saying that under this new SS proposal there would be a widening of the allowable performance mods to include them?

As I understood the original intent for the inclusion of SS classifications in our ruleset, it was to allow members to prepare and practice in their cars to compete in the Parade autocross competition in the SS classes. If that was the actual intent, it seems to me that we should be making changes to conform with the changes in the PCRs that have taken place. We seem to be going in an entirely different direction, and I'm not sure why.

TT

Tom,
No, the conversation we had was to make the SS classes closer to PCR's
Drive the car just as it cam off the showroom floor.
Here are the 2016 PCR's on tires.
“Only original equipment
manufacturer (OEM) wheels as originally specified and OEM tire size as originally
provided and/or specified for each specific model year permitted. For all Showroom
Stock classes, tires must have a tread ware rating of 180 or greater.”


My comment about SS classification was more a complaint about the wide performance gap with in a certain SS class.
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Re: 2016 tire rules for street stock

Postby JayG on Wed Feb 03, 2016 5:06 pm

I disagree
SS does allow FACTORY options and the rules also allow some latitude in tires and wheels.
None of that should be an issue as it is a level playing field as far as tires and wheels. You choose what you want to use and everyone has the same access
Same with other factory options like exhaust or sport suspension.
You can make your car more competitive fairly easily and again, it is a fair level playing field

Where I see an issue is how the cars are actually classified in SS
in some classes, such as SS02, the cars range from NA 993 to 986 S to 977.1 and 987.2.
The 987.2 has more HP at about the same weight, but the biggest difference is availability of a PDK
A PDK does have points added, but in SS points don't matter.
I would ( and will when rule changes are being asked for) propose that at very least 987.2 with a PDK be moved to SS03

Anyone can change tires or add a factory sport suspension or exhaust to their car, but you cannot replace a manual or TIP with a PDK

If you add the points for a PDK (15) to the base points of a 987.2 Cayman (394) its 409 which is in the range of the SS03 cars

Forcing someone to go into a CC class is not the answer. It takes more than just a few simple low cost mods to be competitive
If you look at Jack's options all of them except a PDK are available after delivery

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Re: 2016 tire rules for street stock

Postby jbrennen on Wed Feb 03, 2016 5:21 pm

Steve Grosekemper wrote:Here are the 2016 PCR's on tires.
“Only original equipment
manufacturer (OEM) wheels as originally specified and OEM tire size as originally
provided and/or specified for each specific model year permitted. For all Showroom
Stock classes, tires must have a tread ware rating of 180 or greater.”



That's actually a very reasonable rule set in theory. In practice, it gives control of a model's ultimate performance potential to the tire manufacturers.

I don't think that the point of allowing the minor wheel and tire variances is about letting the owner squeak out a few hundredths of a percent improvement by running 10mm wider, or by running 19 inch wheels instead of 20 inch wheels -- it's about giving all owners a decent choice of tires. It's about taking the performance potential back from the tire manufacturers and giving it to the owner.
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Re: 2016 tire rules for street stock

Postby Greg Phillips on Thu Feb 04, 2016 12:11 pm

jbrennen wrote:
Steve Grosekemper wrote:Here are the 2016 PCR's on tires.
“Only original equipment
manufacturer (OEM) wheels as originally specified and OEM tire size as originally
provided and/or specified for each specific model year permitted. For all Showroom
Stock classes, tires must have a tread ware rating of 180 or greater.”



That's actually a very reasonable rule set in theory. In practice, it gives control of a model's ultimate performance potential to the tire manufacturers.

I don't think that the point of allowing the minor wheel and tire variances is about letting the owner squeak out a few hundredths of a percent improvement by running 10mm wider, or by running 19 inch wheels instead of 20 inch wheels -- it's about giving all owners a decent choice of tires. It's about taking the performance potential back from the tire manufacturers and giving it to the owner.


I would say that the tire manufacturers are still in charge. :surr:
As long as Bridgestone is willing to produce a tire with a treadwear rating of 200 that has the grip of tires with treadwear rating 100 or less, that will be the tire needed to buy to be competitive.

The rules are written with the expectation that tire's treadwear ratings will have some correlation with their grip. But this is not always the case as we have now.
They are a good tire and good price and available in an array of sizes. But their real selling point has been their rating of 200. :rockon:

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