2009 Track Width? also what was 2008 rule?

[Red Tornado]

wanted to see what the increase was and make sure before I start working with spacers, etc..

 

I have over 1.4 inches of room to new rule in front but 1/2 rim size increase to 9.5 and larger tires may chew it up.

[ST#97]

wanted to see what the increase was and make sure before I start working with spacers, etc..

 

I have over 1.4 inches of room to new rule in front but 1/2 rim size increase to 9.5 and larger tires may chew it up.

 

2008 was 73"....isn't 2009 73.25"... you might want to get some R888's and mount them on your current wheels first. the measurements and weights posted by toyo are bogus!

[Red Tornado]

Yeah I need to mount them and check it out.

[Holster Maker]

That's correct, 73.25" for fox/sn95. The .25" is our increase over '08.

Get a 05+ and go to 74.75" or new GTO and go to 76.25"........wow!

[Mystic_Cobra]

I did a quickie measurement of a mounted 275/40-17 R888 (brand new) and compared that to my RA1 from last year. Both are mounted on R58 17x9 Cobra rims. NOT on the car. The R888 was 5 mm wider AT THE FATTEST PART OF THE TIRE-not the tread. I didn't think of it at the time, but I'll pull one of my rain tires and do a few more measurements (tread, height, weight) and post results.

[ST#97]

I did a quickie measurement of a mounted 275/40-17 R888 (brand new) and compared that to my RA1 from last year. Both are mounted on R58 17x9 Cobra rims. NOT on the car. The R888 was 5 mm wider AT THE FATTEST PART OF THE TIRE-not the tread. I didn't think of it at the time, but I'll pull one of my rain tires and do a few more measurements (tread, height, weight) and post results.

 

You are just NOW doing this? LOL!!!

[FlyingDog]

I did a quickie measurement of a mounted 275/40-17 R888 (brand new) and compared that to my RA1 from last year. Both are mounted on R58 17x9 Cobra rims. NOT on the car. The R888 was 5 mm wider AT THE FATTEST PART OF THE TIRE-not the tread. I didn't think of it at the time, but I'll pull one of my rain tires and do a few more measurements (tread, height, weight) and post results.

 

You are just NOW doing this? LOL!!!

You obviously haven't since you've been complaining about the 3/4" wider tires for months. Jimmy's measurements are about the same as the CMC guys found... there is less than 1/4" difference.

[ST#97]

I did a quickie measurement of a mounted 275/40-17 R888 (brand new) and compared that to my RA1 from last year. Both are mounted on R58 17x9 Cobra rims. NOT on the car. The R888 was 5 mm wider AT THE FATTEST PART OF THE TIRE-not the tread. I didn't think of it at the time, but I'll pull one of my rain tires and do a few more measurements (tread, height, weight) and post results.

 

You are just NOW doing this? LOL!!!

You obviously haven't since you've been complaining about the 3/4" wider tires for months. Jimmy's measurements are about the same as the CMC guys found... there is less than 1/4" difference.

 

so you are basing your AI use on measurements from CMC drivers who never ran a 275 RA1 and have radically different suspension setups and spring rates? I have mounted and measured all the combos you can with my wheels and spacers and I know what the dimensions are for 275 and 255's on 9" and 9.5" rims.....I have known since September...

 

I would think you would be more concerned with finding a place to accept your Toyo bucks and isn't charging a premium for it....?

[Mystic_Cobra]

I've been reading the posts and the drama throughout the winter. I just got my first set of R888s myself, so this is my first opportunity to measure. Just adding some more data for the group.

[King Matt]

so you are basing your AI use on measurements from CMC drivers who never ran a 275 RA1 and have radically different suspension setups and spring rates?

So, tell me how the suspension setup makes a tire wider?

[ST#97]

so you are basing your AI use on measurements from CMC drivers who never ran a 275 RA1 and have radically different suspension setups and spring rates?

So, tell me how the suspension setup makes a tire wider?

 

Well, that's easy, the different camber settings will deform a tire sidewall enough to change the contact patch. Picture a 3200lb CMC/2 mustang running -3.5 or more in a 255/16 at 32psi to an 2900lb AI car running -1.5 or less with a 255/17 at 24psi. Pretty typical setups for both. The section width and contact patch width will be significantly different. Have you seen the wear pattern of 255's mounted on 8" rims and 9" rims? the contact patch is significantly different and the same goes for 275's on 9" and 9.5" rims.

 

Seriously dude, unless you have seen all these tires mounted on the various rims and such, you have NO IDEA what you are dealing with. The physical changes in these tires are forcing large changes in setups and spring rates because the way the tire carcass is constructed at the sidewalls. They are like old school "balloon" truck tires. They are wider physically for a numerical identical tire. Sure they might only 1/4" wider when mounted, but the pinched sidewall is like driving on limp noodle. Running at the suggested 38psi hot wears in the middle of the tire badly. Running too low to get a wider contact patch has a tire that "walks" and then wears the shoulders as the tire rolls over.

 

I love how you all criticize but haven't seemed to do ANY actual purchasing, mounting or TESTING of these tires for yourselves. You might want to listen to those that HAVE or do your research on the world challenge teams on the net. Most of you sound like those clowns over at Corner Carvers who think they are experts on everything because they read it on the interweb once without doing it themselves.

 

So who else has seen the tires "peeling" tread out of the middle block when run at full tread along the mold line? Who has weighed a shaved R888 compared to a shaved RA1? Who has measured mounted and unmounted 255/275 on 9" and 9.5" rims? Unless you have, you might want to check your facts. I have even seen as much as 1/4" difference in mounted tread width from Konig Villians to R58 cobra R's because of the way the tire bead interfaces with the lip of the rim.

 

Seriously MK, I am not just talking out of my ass here. I have spent a lot of time in the off season trying to get a handle on these tires before I start throwing money away chasing a new setup or buying new wheels. I have also discussed this with many drivers I respect who have gone out on these new tires and have NOTHING good to say about them other than He who figures out the new setup first is going to own the rest. I have also driven them myself in a few different combos and they felt terrible on those cars and are NOWHERE near what we are used to nor do they wear like iron like the RA1's... Am I an expert...heck no. Have I done more homework than most...you bet!

[King Matt]

You called a guy out for comparing the static track width of the R888 to an RA-1 on the same rim. Look, I don't doubt, and in fact I expect the setup of the car to be very different with these new tires. But to suggest that the static section width of the same tire mounted on the same rim will be wider on a CMC car vs. an AI car because there is a degree or two difference in static camber strains credibility.

[Grizlbits]

AI#97:

 

I realize you suspect the tire is 1/2 - 3/4 wider per side, even though the evidence does not point to that. But that is not where I am going. Have you factored in that even Toyo recommends 1 degree less of camber with the 888 than you were running with the RA1's? By my book, that is about 3/8 per side less of track width. With less camber, and the minor increase of track width should be all you need. You can always run the 255's if you feel the performance of the 275 is like riding on a marshmellow. My opinion is that if suspesion makes a difference with track width, it would be almost unmeasurable. Your results may (do - I guess) vary.

 

Personally I consitantly run have run 335/30/18 Toyos with an 11" wheel on my AIX car when everyone said it wouldn't work. It works fine. I also have run the same setup on Hoosiers and even 345/35/18 Hoosiers on the rear. I have compared the 305's vs the 335's back to back and only really noticed a few tenths faster with the 335's. The 335's do run cooler and last longer though.

 

I have to go through the same learning process you guys in AI do in the Spec Miata that I drive. But that's what we do and that's why this racing thing is fun. Setup and racecraft are all part of the game.

 

I realize, I think, your point. Toyo seems to have brought an inferior tire. Time will tell. What I don't really get is what you want the series to do about it. Or are you just venting at Toyo? Or are you venting at the rules process because you didn't get a 3" width increase?

[D Algozine]

Most of you sound like those clowns over at Corner Carvers who think they are experts on everything because they read it on the interweb once without doing it themselves.

 

Funny stuff..

You mean those stupid guys who are mostly engineers, and many who are race car fabricators and/or work for professional race teams, yah what do those guys know?

Caution: Wide sweeping generalizations are a red flag

[ST#97]

AI#97:

 

By my book, that is about 3/8 per side less of track width. Don't you mean MORE track width with less camber assuming same wheels same spacers?,

 

 

correction? in bold...?

 

Yes, I think Toyo gave us a lame duck. Am I venting...sure why not, it's causing me to spend time and money to figure out something that didn't need to change and wasn't in the best interest of our wallets or performance which I personally think hurts our series considering car counts are in the crapper because of costs.

 

Venting on the rules...? Maybe? I think it would be nice if we could go to a 10"+ wheel to take advantage of the additional width of a 275 R888 and possibly INCREASE performance, but that causes other problems with wheel offsets and suspension clearance and would require a track width modification on Mustangs as well as a custom wheel source...unsure of the other cars. the FFR guys seemed to keep it simple and went to the 255 tire instead of the former 275 as a max...maybe they were on to something?

 

I suppose my overall rubb at this point is we got this shoved down our throats by Toyo and there wasn't a heck of a lot reasoning behind it. It's not like Toyo is marketing these tires to the general public for street use and refreshed the tread design to sell more tires...? I don't think I have ever seen Hoosier introduce an inferior tire to increase sales....but I could be wrong...it's been 5 years since I have run them.

 

Honestly, the entire argument for me now is a moot point and I am wasting all of our time beating a dead horse. We can't get enough cars in AI in our region to even get $5 in toyo bucks so I am considering running in ST/SU on hoosiers and dumping the AI stickers so I can actually get tire money there. We all have our little problems to complain about I guess.

 

 

And Dave, yes. I like taking shots at the corner carver nerds!

[Grizlbits]

By my book, that is about 3/8 per side less of track width. Don't you mean MORE track width with less camber assuming same wheels same spacers?,

 

No, actually I don't. The track width is measured a few inches up on the wheel on the bottom. Less camber will move the bottom of the wheel in, thus reducing track width. Another added bonus is that you may be able to run less spacers because you will have more clearance between the inner/upper portion of the wheel and the coilovers - if you run them. That is usually the limiting factor on the inside assuming your brakes will clear the wheel also.

[FlyingDog]

You called a guy out for comparing the static track width of the R888 to an RA-1 on the same rim. Look, I don't doubt, and in fact I expect the setup of the car to be very different with these new tires. But to suggest that the static section width of the same tire mounted on the same rim will be wider on a CMC car vs. an AI car because there is a degree or two difference in static camber strains credibility.

Bingo!

[JWL]

[Red Tornado]

In april I am getting my first set of 888's and believe me I will measure everything, look at camber and test the tires.

I have detailed records of all the tracks I will run after so I should have detailed reviews than

[ST#97]

 

 

come on John, if we weren't all a bunch of unruly children...you would get bored with all the silence!

[JWL]

It's true. I love you guys (no, not in that way you gobblers) and the above was intended as a little ribbing.

 

I agree that the 888's will need some setup alterations, but other folks seem to be getting to work on finding how they work best. As I said earlier, if the 275's don't work on the allowed rim size, perhaps the 255's are the sauce.

 

-JWL