Street tires in IT??

AS most of my ideas are considered "absurd" , I have been lurking this thread. Plus I am really focused on some patent searches.

First. I moved my IT cars to Prod for the tire issues. I dont want to buy HOHOs to race for some plastic.( and I cant rent a car on Hoosiers and clear any cash, one flat spot ruins it.)

The 180TW tires are slower than any DOT race tires .
I get 1.22ish lateral G on the Toyo SM tires, fitted to my Golf, On concrete.
I get about 1.08 or so with the 190TW Dunlops, same turn , same car. (true that some lower spring rates may bring up the max grip a bit on the lower grip tires.)

My basic rule set for the "ITX" or ITJ class allows the SCCA legal IT cars along with the limited prod cars to run on the 180TW tires.

Many Chumpcars are IT cars with street tires. These guys have found that street tires are a nice way to race. The tires last 20 hrs or more. ( depending on aggression level. )
The TW rating should be 180 or higher, to match the lemons/Chumpcar rules, not 200.
Many more tire choices at 180. maybe 10 tires for the SM size

The best way IMHO to execute this idea would be to have a pizza party sat eve for the 180TW cars . Make it look like the bestway to race and it may work out that way. Sell it.
 
As an outsider looking in, moving towards cheaper tires seems like a no brainer. I agree with others that running $1000+ short lived hoosiers on IT* cars seems silly. IT is obviously not alone, with slicks on FF etc ...

I'm not sure why the jump to 200+ tires though. I would think making it 100+, leaving NT01s and RA1s would make more sense and attract more people. The tires are cheaper than hoosiers and last a lot longer - the overall tire cost would probably go down by a factor of 4.

I agree with the others who suggest just making it a gentleman's agreement within IT* to start. You don't need any official involvement at all. Just a group of drivers in each region to get it started, appoint a leader, and get the word out. A website would be nice to post points, and "who's coming". If guys want to chip in for a season end trophy - fine, otherwise just post a picture on the website with "season champion".

Just get it started and see where it goes. If only 10% of the IT cars run harder tires and it fizzles out, so be it. Maybe the numbers become higher and it gains some momentum ...
 
So you saying to do exactly what the NER IT7 guys have done

100 treadwear Nitto NT-01
Season points, and year end trophy
Gentlmans Agreement so as to not drive off new competitors that buy cars with tires already.
buy tires at Walmart and use 1 set for up to 2 seasons.

Sounds like a great idea. Sounds just like the idea I posted on page 1 that is in practice now. Hmmmmmmmmmm:smilie_pokal:

Sorry for the sarcasm, its been a long week.
 
Haha, that's ok Dan :).

We are going to start a 200TW class, and yup that may be the name of it.... Eligible to all IT cars but focused on ITR and ITS since I know people interested in it... More to come soon. I may run in my new class in September. This will not be an SCCA class, just something we are going to do on our own as a gentle men's agreement similar to what you did.

Stephen
 
After 4 years of running @ 190, the new Chumpcar rule @ 180 is a vast improvement for tire choices. ( even tho I still have 12 of the 200) :)

Again, please look at 180 for the amount of cheaper tire choices.

There may be only 1 or 2 tires @ 200 that fit your car but 10 options @ 180.
Choice is good. PS, edit. many of the 200-300 tw tires will chunk without shaving. Most of the 180 class tires are ready to run.
 
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2 cents. I am in support of moving IT to 180TW even w/o adjustments. After much thought and for reasons stated above, including the reasons some provided why we should not be going to 180TW, I can argue why we should.

Now, I need to get ready for NJMP. :) Bye!
 
While I think this is a great idea, I doubt it will get much traction beyond the gentlemen's agreement stage. I would suspect that the IT market is a large portion of the R6 market. Hoosier won't take loosing that much revenue lightly.
 
one foot, one vote!!

I was always an optimist. Don't forget whence we came!
Enough "feet" voted for the original IT.
They still have the power.
"Feet-do yo thing!!"

PS: I just replaced the OE 140TW tires on my 06 GTI with 180s-they were too expensive and wore out too fast; went through 2 sets in 53k, and I put snows on for winters! I'm with you in spirit!
 
I will be creating a double dip class that my brother and a few friends may race in. We will be in STL and/or STU as far as SCCA is concerned and if people like it I will go to our region about it. Just a gentlemen thing for now. I can post up my ideas if people are interested.

Stephen
 
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After 4 years of running @ 190, the new Chumpcar rule @ 180 is a vast improvement for tire choices. ( even tho I still have 12 of the 200) :)

Again, please look at 180 for the amount of cheaper tire choices.

There may be only 1 or 2 tires @ 200 that fit your car but 10 options @ 180.
Choice is good. PS, edit. many of the 200-300 tw tires will chunk without shaving. Most of the 180 class tires are ready to run.
Stephen et al.: MM makes a very good point. Even though you think it's just a small agreement, look further down the road when you choose your line in the sand. I said 200 as a talking point. Based on no significant research.
Look around and see what choices exist, and make a rule that encompasses those choices. Later on, it's going to annoy folks if the line in the sand is moved.

At least try and get it close now.
 
For sure... looking to use some ideas from NASA that is working for them. Yes I know I can't use that name here but so far it is working out on paper:) testing the ideas in September on a casual basis...

Stephen
 
http://forum.chumpcar.com/uploads/gallery/album_42/med_gallery_1344_42_148819.jpg Tires/sizes price
FWIWthere are not many tires TW 180 in 13 or 14 rim sizes

At this point you could build upon history and not repeat past oversights. IE spec the tire width and not the wheel width( or both). Sounds a little absurd I know but this may help avoid the cantilever tires like the A6, 245/40/13 , made to fit the rim size and obsolete the other tires. Prod has the same issue today that they are just starting to work out of.( 10in tires on 7 in wheels, made just for this rule in the US .)

As most of the world /USA road racing is going to this sort of rule,, It would pay to outlaw any tire clearly out of range grip wise and not in the spirit. Disregard any tire contingencies. Dont take money from anyone..
IMHO, MM
 
for the time being, operating under IT rules means operating under IT wheel width rules. that pretty much locks you into a 205, MAYBE a 225 on a 6" rim in ITB and C and 225 MAYBE larger in ITA and S. R can get a lot bigger, maybe 245 on an 8.5" rim.

I agree in theory with Mike, though. long term, if this takes off, you'd want to lock the class to a max section width not a wheel width. this could be done today in some localized sub rules, but the gentlemen's agreement version of things will want to keep existing rules until they have a leg to stand on in terms of demonstrated participation counts. this means that ITB and A are likely to be the bogey classes for the success of the gentlemen's agreement as they are most likely to work well on these wheel/tire fitment options.

agreed on 180TW. though I think 200 is probably good enough in terms of fitments, I'd want to maximize crossover and rules equality between these ideas and established TW rating minima as much as possible.
 
My 2 cents...

180TW as it matches LeChump. LeChump teams can run the same tires in both SCCA IT-Street & LeChump if they want.

Definitely go with tire section width vs. wheel width limits.

I'm seriously thinking of what I'll be doing next year. Maybe run the LeChump in STX or make it STL legal. Double or triple dip to share weekend with teammates. Run ECR series in STL on street tires.

Or - Maybe buy a cheap IT car for club race weekends and run on street tires.
 
for the time being, operating under IT rules means operating under IT wheel width rules. that pretty much locks you into a 205, MAYBE a 225 on a 6" rim in ITB and C and 225 MAYBE larger in ITA and S. R can get a lot bigger, maybe 245 on an 8.5" rim.

I agree in theory with Mike, though. long term, if this takes off, you'd want to lock the class to a max section width not a wheel width. this could be done today in some localized sub rules, but the gentlemen's agreement version of things will want to keep existing rules until they have a leg to stand on in terms of demonstrated participation counts. this means that ITB and A are likely to be the bogey classes for the success of the gentlemen's agreement as they are most likely to work well on these wheel/tire fitment options.

agreed on 180TW. though I think 200 is probably good enough in terms of fitments, I'd want to maximize crossover and rules equality between these ideas and established TW rating minima as much as possible.

I am totally agree with you. You are 100% good here that the gentlemen's agreement version of things will want to keep existing rules until they have a leg to stand on in terms of demonstrated participation counts.
 
OK so I am putting PEN to paper today!! Tim and I ARE going to race eachother in group 7 in a few weeks using our new class that we made :)

It is called: RST (Racing and Street Tire)
We will follow ALL Improved Touring Rules including rim widths and current listings. We don't want to re-invent the wheel to much and have ZERO interest in redoing current weights listed in the GCR. Our goal is to race against eachother (I am in ITR and he is in ITS) AND introduce longer lasting Street Tires like the Dunlop Direzza ZII so that we can race more often on a budget!

YES this is our own gentlemens agreement class and we are actually racing in STU as far as SCCA is concerned. BUT we are going to have fun and we welcome any input and or participation from others!!


Here is how we decided it will work: (We will probably do tweeking after this event)

RST Power to weight Ration Base weight goal is to be equal to ITS currently. So the following calculations will need to be done if you are in a different class BEFORE using the Tire Handicap.

ITR cars will ADD 14.7% to the ITR spec weight for the car.
ITS cars will STAY at ITS spec weight for the car.
ITA cars will SUBTRACT 12.4% of the ITA spec weight for the car

* For example the RX8 in ITR is 2850lbs so to run in RST without a Tire handicap it would run at 3,269lbs

Tire Handicap rules:
AFTER determining the base weight above you will then take the following modification to the weight of the car.

1.) The following DOT-approved R-compound tires and those with a UTQG treadwear rating of 40 or less will NOT HAVE ANY REDUCTION IN WEIGHT:
Examples: BFG R1, Goodyear Eagle RS AC, Hankook TD, Hankook Z214 (C90 & C91 compounds only), Hoosier A6, Hoosier R6, Maxxis RC-1, Goodyear Eagle RS, Hankook Z214 (C71, C70, C51, C50), Kumho V710, Grand Am Continental Tire Sports Car Challenge tires, Toyo Proxes RR

5) DOT-approved R-compound tires with a UTQG treadwear rating of 41 to 130 WILL GET A HANDICAP AND REDUCE 5% OFF OF THE BASE WEIGHT
Examples: Kumho V700, Michelin Pilot Sport Cup, Nitto NT01, Pirelli PZero Corsa, Toyo R888, Toyo RA-1, Yokahama A048,

6) DOT-approved (non-R-compound) tires with a UTQG treadwear rating of 131-200 WILL GET A HANDICAP AND REDUCE 8% OFF OF THE BASE WEIGHT:
Examples: Bridgestone Potenza RE070, Dunlop Direzza Sport Z1 Star Spec, Dunlop Direzza ZII, , Kumho Ecsta XS, Hankook R-S3, Toyo R1R, Yokohama Advan A046 & Neova AD08,

* Using the same RX8 example if the car had a tire with a treadwear at or above 131 it would use the following to determine weight:
2850 * 14.7% = 3269lbs then 3269 * 92% = 3007lbs

For reference here is the class structure for lbs/hp in Improved Touring
ITR: 11.25 lbs/hp
ITS: 12.90 lbs/hp
ITA: 14.50 lbs/hp
ITB: 17.00 lbs/hp
ITC: 18.84 lbs/hp

For reference here is the class structure for lbs/hp in NASA PT
PTB 10.25 lbs/hp
PTC 12.00 lbs/hp
PTD 14.25 lbs/hp
PTE 16.50 lbs/hp
PTF 19.50 lbs/hp
 
why not simplify it to "Run street tires of 180TW or higher in IT using existing rules and classifications"?

if it's popular, you have people to run with. what you're proposing seems like an awful lot of work, not to mention weight reductions are not always achievable. ITA cars in your system need to loose 20% of their ITCS weight if on street tires. that's 200# for every 1000# of ITCS weight. few if any cars will be able to do that. and you didn't even include ITB, a class you used ot run and know is popular in your area, and one of the more cost sensitive classes, too. What you've made is effectively equalized ITS/R with compensation for tires.

I don't get it.
 
Reality is that a second class to take off with only street tires will be tough without participants... same logic as stl.

So using the double dip logic that is working for stl I decided that we should try something that double dippers would be able to do without purchasing anything. It would help the region and help create interest seeing street tires race against r comps. I think creating a class that its cars can run as is, especially where some of them are running in stl already week help create interest and some fun racing.

Also remember this is an interest that Tim and I specifically had to race each other so it certainly doesn't benefit everyone in every class.
 
I'm with you on double dipping, running closer to heads up with your friend, and helping the region.

I'm not with you on the need to change rules to to that. but I hope the endeavor works out well for you guys - I am interested in seeing the street tires on track and increasing interest in same.
 
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