1 melted hub ring... Didn't melt the other because I forgot to put it on...

Anyone else's Kumho's do this.. People tell me its from low air pressure, but its over 42psi hot, and I am wearing off the inside of my tires, not the outside..

One thats a little worse off the rear...

And another rear, basically ran like this all day Sunday, thats why I zeroed my toe..

Rotors anyone..... Trust me, they got hot... They were Glass smooth using XP's, groved up and cracked with one race on Blues...



Ball joint boots anyone, they were just fine before this weekend, I really think sunday did them in...


Now, I wonder if my ABS will ever work again...


Oh yes, and the one that did me in... From what I can tell, the heat cracked the boot up, grease went flying, and dried up, it is BONE DRY inside the boot...

Time for some SERIOUS ducting!

 

Corey,

Let me know if you ever need an extra hand. I have just about decided to build a road race car. I would like to start getting some experience.

Josh

 

Something as simple as a little air deflector zip tied to the lower control arm would help get some more air onto the ball joints, outer CVs, and so on...

 

I believe Tire Rack offers metal hub rings. A friend of mine only uses metal because he's has the rings stick to the hub and make it hard to get the stock non-ring using wheels back on.

 

Corey look like you got the same problem as me, We drive to damn fast for our cars Good job on all parts listed above If you need any help puttin it back together call me I'm right up the street.



[Modified by 89civicZC, 1:51 PM 7/4/2002]

 

Good lord man! For some strange reason, I don't feel so bad now.

John -- who has a fresh set of rotors on the car, and Blue's on the way.

 

i am anything but an expert but that much wear on the inside should mean too much camber, my kuhmos look like that when the flat spot from brake lockup, just not corded that badly or consistently around the tire though......less camber would have to improve that wear though (although i am assuming you have camber plates)....that is pretty screwy looking tire wear

 

Good god! Those are some nasty looking pictures. Keep up the good work!

 

Just leave them off. They just make it easier to mount the wheel, the lugs (and frittion of wheel against hub) bear the load, not the center rings.

What pressure are you starting at? Looks like a combo of too much heat and too much negatie camber. I assume this is a front?

Hmm, this one is too much heat and too little camber.

Tell me which tire came from which corner, that's some crazy wear. My guess is you just plain overdrove them. How long and how many sessions?

Everything else is a matter of ducting. My guess is the heat off the brake is making everything else fail. Use the most ducting you can - ITS limit is a single 3" max inlet to each brake. Not sure if H-C has a similar limit. And if you can, add some air deflectors as mentioned above.

 

Corey,

Don't forget the spoiler.

I already have it half rebuilt ........... Do you need them before CMP!

Back to the shop.

Like my signature?


[Modified by JohnW, 8:59 PM 7/4/2002]

 

The inside tire wear can be from too much body roll. Lifting and spinning the inside front.
I had this problem at CMP and it's why I went to teeth shattering spring rates at Summit. Solved one problem and created another.

Tire Wear... Both Corey and Brinson's experiences with the new Kumhos back what I've been hearing... They're crap. Brinson effectively killed a new set of Kumhos on a car that is identical to mine (except it's a bit lighter than mine). I ran my second race weekend on the same Hoosiers and they are ready for a 3rd, maybe a 4th. So, the Kumhos are cheaper to run??? I think not.

BTW... No more bitching about how CMP tears up brakes. Summit was much harder on my brakes in 2 days than CMP was over 3 days.


[Modified by Catch 22, 5:48 PM 7/4/2002]

 

Ok, that pealing tread, is from the OUTSIDE of the tire, but the inside is wearing out quicker...

So far, I have bought 6 of these Kumho's for 3 race weekends, they are all shot now... Scott, I forgot to tell you I ran summit the weekend before H-C, in the USTCC, and used the XP's and tires... So XP pads, 1108 compound, lasted 3 days, rotors were in great shape.. I love these tires, other than the fact that when I seem to start out with 30lbs, they peel away, but are really fast, at the expence of destroying the tire..

 

I've got about 2/3rds of my XPs left on the car after this past weekend. My Hoosiers also lasted rather well, without the bad inside shoulder wear you both seem to be getting. And I'm driving a one wheeler peeler.

FWIW, I do run Panther Plus' out back. Perhaps that is helping, since the rear brakes are actually doing something now?

I don't get it. Maybe I need to drive faster.

 

Corey,

Wow, you are on the other side of the country but it looks like picture of my car from last weekend...melted ABS wire...melted ball joint boots...fragged rotors. The braking on our cars is the weakest link.

The tires I am afraid to say are simply overdriven. When they start to go off and get greasy and you keep pounding on them thats what they end up like...the car can go faster....damn push... must go faster....blister blister blister. This is why I like racing in the rain!

Victor Penner

 

So, you're going from 30psi cold to 42psi hot? Try starting a bit higher, maybe 33psi. This should hep keep the tire temps down a bit (low pressure cold = lots of tread squirm = overheated rubber).

I hadn't realized those were the new Kumhos, if so, call the Kumho rep and tell them what's up. I've only seen wear that bad on the old Victos on poorly set-up cars.

 

Um, My car is poorly setup... The front shocks are sitting on the bump stops... Once again, the peeling of the tread is on the OUTSIDE of the tire... I started the race on Sunday with 32psi cold tire pressures, and the car felt like crap! No grip anywhere.. My times show too.. 1:28.3 qualifying (3 Laps) VS 1:29.0 (19 laps) race...

p.s. heather is awesome

 

Not picking on any individual at all but there is another lesson to be learned from all of this...

Brakes turn kinetic energy into heat energy and shed it to the atmosphere. Thermodynamic rules make this process time-dependent, so lengthening the time (and the distance) that the brakes are on can have a dramatic effect on longevity. Assume that you reach a speed of 100mph at the end of a straight and need to be going 60mph to survive the next corner. If you shed the energy required to do this over 3 seconds rather than 2, you increase the amount of time by a huge margin (speaking relatively). Not all of the heat energy is shed in that time (some of it hangs out in the brake rotor and other parts, to be transferred to the air later) but you have 150% of the time that you would otherwise, to get rid of it...

Ducting is obviously a good idea but is a pain in the butt to put together, is easy to rip off of the car in an off-course, and gets neglected. Remember, though, that we can do a lot to make the brakes last by not using them to the max every time we step on the pedal. The whole point is to cover the maximum distance over a set period of time, or cover a prescribed distance (more than one lap!) in the minimum time. We increase our chance of doing this if we go a little easier on the brakes...

Kirk

 

I'm having some 'issues' with my ecsta v700's for autocross. Squirmy tread, easily overheats and gets greasy and chunks, poor 'feel' (as subjective as that can be). However, final judgement will be reserved until i wear this current set in and i get a set of the "new" tread compound that is supposedly coming soon....

Until then... i wish i had the victoracers. By the way, how do the 'new' kuhmo compared to the 'old' kuhmo stack up for you Corey?

 

j00 are my her0.

Will
-who uses 'wear' itmes as well as Corey...

 

Traction is the same in the tires (I have the "old" victoracer compound in my Ecsta's) They only reason I go with these tires instead of the victo, is because I can use a 225/45/15 that weighs 20.5lbs, vs 225/50/15 that weighs 24lbs....

So what I gain, is less weight, and much better gearing.. I ran the Victo's and Ecsta's back to back at summit.. Much better gearing with the Ecsta's, I was almost tapping out 5th with them on the main straight, where as the Victo's, I was nowhere close...

 

Just don't use your brakes so much and then you'll go faster

You need to be thinking about those bearings also.

 

I second that!!

Corey, my v700's did do about the same thing. I wasn't running as much camber as you apparently, so mine happened pretty much down the center and worked it's was to the sides. I don't know about you but I could actually feel big chunks of my tire come flying off and I would loose some traction as a result. I do love these tires though, I was a little unconvinced at first but as I got to know them better I began to fall deeply in love with them. I was running 44psi hot in the front and 39psi in the back at the two seat times I did back in March. The temp at the second day was 94-99 degrees through out the day (pretty similar to last weekend) and my tire temps were 122 deg in the front and 120deg in the back. Does this at all sound like I am on the right path?? BTW the car is an 02 ITR. If you could provide an insight that you are willing to part with I would appreciate it. TNX.

 

I'm w/ Crack Monkey. Blow up the fronts. Hard. You just might be surprised

Warren

 

McLaren: track tire temps should be somewhere around 180F hot. This is fresh off the course on a hot lap.

Warren

 

First time out autocrossing the 'new' kuhmo tire (i assume 'old' tread compound) we had some chunking issues. Ran the tire initially at 36(F) and 38(R) cold pressures. Coming off of a run they would be at 40+(F) and 40(R) - and the middle of the tire in the front had chunked up quite a bit. There is noticeably less tread in the middle of the tire than there is on the outside edges after this (though its not bad at all). I'm running 225/45/15's on a 15x6 wheel, FWD Saturn. Was there not enough pressure in the tire initially? Too little? We dropped the pressure down for the next few sets of runs to 32-33(F) and 36(R) and the chunking seemed to stop, at least for the day. They were at 36(F) 38(R) at the end of the run and they felt a little better, but i dont have enough experience with the tire yet to really judge that.

I am generally not abusive towards tires, my last few sets of kuhmo's wore pretty evenly and i got good wear out of them, and when the 'new' tires were doing this i wasnt doing things like tire smoking understeer either.