Hi all. So we accept the fact that there is no negative camber from the factory for our MINI’s. I’ve done the “free” negative camber adjustment to my fronts but I am still destroying the outer edge of my front tires when I Autocross. Other modifications to my ride are:


1. Tires are Bridgestone RE-11a 225/45 on 17x7 wheels. Previous tires: Kumho Exsta XS, Hankook RS-3, Michelin Pilot Super Sport.
2. I change pressures at venue and range between 36-40psi up front and 36-42psi in the rear.
3. I have a 3 position rear sway bar set in the middle setting.
4. EBC Yellow brake pads on factory rotors.
5. Koni yellow sport shocks. Front setting for Autocrossing I use 1 full turn from full firm to 1.5 – 2 full turns from full firm. Rears are set to the middle setting and due to location, I don’t change them.
6. As said before, the “free” negative camber adjustment which may be worth up to 1º.


I tend to be “ham fisted” and “ham footed” when I Autocross but I’ve done well with results winning my class and finishing in top 10% for PAX adjusted Fast Time of Day.

How do I stop destroying my tires?


Opinions welcome!


Thanks.

 

Are you trying to stay in street class? There aren't any options. Write to the SEB and ask them to allow one form of camber adjustment in street class. It was on the table as a rule change when the "Street class proposal" came out but eventually was dropped.

http://crbscca.com/

If you're not worried about staying in street class some IE adjustable camber plates would help greatly.

 

Way back in the olden days I did that sort of thing a lot and if I remember correctly everybody brought extra tires with them. Seems that there was something predictable about solo and destroyed rubber that was just an accepted part of the project. Brake pads and bushing of all different sorts took a pretty serious beating too.

 

SOLO is going to chew up tires.
Try upping the pressure on the front tires. There should be less roll over that way. I am running Dunlop ZIIs and never run lower than 42.

 

v10climber: I'd like to stay street class with my friends and STX is really competitive here. I'd go all in with camber plates as you suggested, plus coilovers if I want to play with STX.
If I do just the camber plates, would you say that I could get twice the life out of a set of front tires? If not, then just even wear across the tread?
You have a preference to camber plate manufacturer?

Thanks.

 

Mini2na: I “chunked” my Michelin’s (see pic) at a track day and couldn’t get DZ II’s on short notice. What other tires have you used for Autocross? Would you recommend the DZ II?

I used to run 40psi up front but my sidewalls still showed rollover wear and I got some better times with less pressure. If there was a 40 series sidewall instead of 45, I’d buy that.

Next event, I’ll bump up to 40’s again and put in some runs.
Thanks.

 

how often are you flipping your tires? i had 60 runs on my ZII's and decided to flip them - pics: http://r56hs.com/2014/04/18/thoughts...-wear-updates/

i really really wish they kept the camber allowance.. would have helped tire wear so much - i'd be surprised if you got that much camber from the camber trick, mine are pushed all the way in and i've still got nothing as far as camber goes (http://r56hs.com/2014/04/09/alignment-woes/). i think all we could do are camber plates though. tough for our macstrut cars to do much else.

does anyone know why they dropped the camber allowance? too expensive/not in line with the stock/street philosophy?

 

Newb question here: How much lapping (how many laps) did it take to destroy your tires like that?

 

I don't know about twice the wear but I can tell you we get probably 170 runs out of a set of Z2s but we're also running around -3.2 degrees of camber. I think the Ireland Engineering camber plates are the only ones that can use the stock springs.

Holy crap! Been there done that but it was on the STI. You're rolling over waaay too much. You need to be closer to 45 in the front. The Z2 Star Specs are great because they have stiffer sidewalls than some of the other tires out there which makes them a little more forgiving for camber challenged cars.

Definitely spend the $80 halfway through the life of the tires and start flipping them on the rim. Should help a lot with life.

I wish they would have kept the camber allowance too. I never heard any valid justification for dropping the camber allowance. I'm guessing the membership got so stirred up with the proposal that they dropped all the other things and just kept the street tires and +-1" rule.

 

I found RE-11 liked higher pressures. We used 205/45-16 and they seemed happiest around 46/45. That was also where the tire temperatures evened out.

After we increased the pressure and got an alignment the wear evened out considerably. But the outer edge wear was still the limiting factor on the life of the tires. We got around 100 runs out of them, a whole years worth.

 

We've used RE-11, Rivals and ZII. The ZII work best for us. I would avoid RE-11A we've only done one autocross on them and they suck. The RE-11 are now available in 200 treadwear, but they're slower than the Rivals or ZII.

The fastest guy in street locally (in GS) runs RS-3, makes me wonder if they're worth looking at, now they're 200 treadwear.

 

I run 245/40/17 Rivals on my 17x7 and they like 46f 51r

But that is somewhat due to the slightly pinched tire. I would still up the pressures on your tires some though. Maybe 42f 48r

 

Those Michelin Super Sports had 44 autocross runs before the track day. During my second 20min session on Atlanta Motorsports Park's main straight, it sounded like I was on a gravel road all of a sudden. I realized the track was clean, but I was making a mess of David Hobb's "Clag" on track. Pulled into pits and moved fronts to rear and finished the day.... carefully.

 

Regarding flipping the tires, not enough. I'll flip these RE-11a's after our next Autocross event.

 

Are you running 245/40/17 on all four corners? Any scrubbing?
I used to put the rears up to 45psi before I got the stiff rear anti-sway bar. Since that addition, my car rotates pretty well.

Mind if I ask what setup you are running? Struts, springs, sway, spacers, other suspension kit?

I'd like to get to a baseline suspension friendlier to the front tires, then I can concentrate on the loose nut behind the steering wheel.

Thanks.

 

Sport bar up front, hotchkis comp rear, 17x7 et42 (no spacer), JCW springs, koni singles

No real rubbing. You can see where the rear tire has barely rubbed on the rear trailing arm a couple times, but that's it

 

Jeremy's setup is about what most stock/street class minis run. Without seeing the tire wear I can't say what you can do. But if you're really destroying the outside edge try adjusting your driving and tire pressures.

I found that I could run about 48 hot pressures up front and 58 in the rear and have decent balance. Running them lower by about 6psi was only a few tenths faster and only reserved for big events. Because it killed tires.

 

Thanks for all the feedback guys! Here's an update:

I did the PDX/HPDE at Road Atlanta this past weekend 5/17 and the car did well. I moved the rears to the front since I've got significant wear showing from 4 autocross events this year. I adjusted my pressures to 40 in the fronts and 41 in the rears. After the two runs I showed 46psi in the fronts and 45psi in the rears hot. The wear is ugly. I have pics attached.

When I drove home, I noticed some odd "flapping" sounds at random speeds. Sounded like some plastic under body part loose and swinging at the car's body. Stopped to check it out. Saw nothing out of the ordinary. I took off the track tires at home and put on my street tires and saw what was making the flapping noise. Parts of the tire are coming off in long pieces. They look like licorice whips (see pics).

I'm tempted to bring them to the tire shop and see if Bridgestone wants to take a look at them as they are falling apart in a structured way. I question the integrity of the tire's construction at this point. I have gone through Kuhmos, Hankooks, and Michelins without this kind of failure. Have any of you seen this kind of rubber/tire failure? If not, then I question my driving as the culprit and will seek out professional instruction to remedy the tire punishment bad habit I have formed.

Also, I made it thru the entire autocross season on my Kuhmos and the following season on the Hankooks. The Michelins.... not up to the challenge. The Bridgestone RE-11a's..... Definitely NOT up to the challenge with only 4 Autocross events and 1 PDX with total track time of 40 minutes.

So, questions to ya'll:
1. What tire can put up with more abuse? R1R, Rivals, Direzza? I understand the Direzzas are done and a replacement is eminent.
2. Will camber plates solve this? Key word is solve. If I leave D-Street class, I will need to go full monty on coilovers, camber plates, etc. to be competitive.

Enjoy the pics and opinions welcome!

 

We had that happening the first time we tried RE-11A tires. Its one reason why I don't like them (another is I, or the tires, were slower with them, about 2s a lap). The first time we drove away from the track I had to stop to work out what the noise was, the strips were coming away from the rears so badly. After a couple of track days and an autocross, I gave them away.

We've had very good luck on track with RE-11 tires (no A). They're available again as 200TW tires. We had a little of that, but no where near this bad. For autocross, Rivals or ZII have done better for us, we prefer the ZII. I've also used the ZII on track and they do pretty well, at least as good as the RE-11, if not better. You might be able to find some still in stock our 16" were out of stock, but we just got some 215/40-17's.

We've never tried Rivals on track.

Camber plates couldn't hurt, but I doubt it'd fix that issue.

 

Are you sure those aren't strips of OPR you picked up at the track?

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I'm not sure if they're from the tire or other people, but the RE-11A have them worse.

 

I thought it was clag or picked up rubber at first then I looked at the pieces starting to pull apart from all the tires. It's like string cheese. Look at the piece in picture #2 circled in red as, "rubber whip about to happen". I found 5 more babies like this on the other tires. Can't wait to run my next autocross and hear them slapping and flailing about.

I'm looking for professional instruction at this point. None of my friends or competitors have this kind of tire meltdown so I need to start with the loose nut behind the steering wheel. Any of you have experience with a driving school? Good, Bad, other? Any recommended organizations? I live close to Road Atlanta and sent an email to Skip Barber for insight on what course would best fit my needs. Correct bad habits, drive my tires close to or at the limit, and develop smoothness.

[FONT=ARIAL,HELVETICA][SIZE=2]"There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games." - Ernest Hemingway[/SIZE][/FONT]

 

No expert, but I'll relate my experience.
During my early autocross years I has Kuhmo XS tires. After hot days on the asphalt and me flogging my MINI, I would get the "balling up" of rubber on the tread areas. (It never string cheesed on me though). As I wore the tires out the rubber balling slowed down. I'm not sure if I was getting better at driving, there was less rubber to ruin or the rubber properties were changing with cycling.
I now have had Dunlop ZI and ZIIs and have not experienced this phenomena to a great degree again.
Here are some thoughts to ponder:
Is your car understeering? This really heats up the front tires.
If understeering, are you turning back out of it rather than turn in more? This still takes effort to fight the natural urge to turn the wheel more when the car is not going around I want it to.
Is your alignment too extreme?
Are you burning out at the start or on corner exit?
Are you spraying your tires in between runs? Most tires like some heat in them, but some less than others.


I have experienced all of the above as I have progressed in autocross. Have someone or 2, ride with you.


Good luck.

 

here are my tires after ~120 runs and 2k street miles:









i'm trying to decide if i wanna just run these until they cord, or sell them a little early to a guy who gets decent camber and he'll get plenty of use out of it, etc... thoughts?

 

You'll probably heat cycle them before they cord. Looks like they're still in good shape. I'd keep running them. Can you still get the z2 in your size now that they're discontinued?

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