AKKutz

Anyone familiar with Putnam Park?

I ran an HPDE this past weekend. Started off with a new set of NT-01's 245/30/18 and 285/30/19.

Cat is '16 C7 Z51 with LG sways, AMT camber kit, DSCSport controller.

I was running 1:20's. I ran 7 sessions over two days.

10 turn track, less than 2 miles, 8 right handers, 2 lefts.

I tire trailered the tires.

When I went to swap out tires, I started from driver's side rear, to front to pass side rear to front. Three of the four tires look awesome. Fourth tire had twice as much wear, this being the right front tire.

I started cold tire pressures at 28 and found hot I was getting higher pressures on left side by 1 psi, so I adjusted to running 28 on left and 29 on rear. Hot pressures btw 35-36.

Question is why so much more wear on right front tire?

Suggestions?

cagotzmann

Pictures ? Is it even wear ?

Kubs

Pictures would help. Is it just shoulder wear or across the whole tire? Can you feel a sharp edge on one side of the tread blocks rubbing your hand back and forth?

AKKutz

Top picture is the of the right front tire.
Bottom 2 are left front to left rear, right rear. They look good for a 2 day event.
-2.0 camber, +7.5 caster, -.5 toe (atleast what I was shooting for, did my own alignment).
Running LG front sway in the softer of the two options.

mikeCsix

A tire temp (IR) measurement would tell a lot about uneven heating across the surface of the tire which is a strong indicator for alignment issues. If you are doing your own alignment, the toe could have been off accelerating wear with that much camber.

63Corvette

Are the two (2) left turns (pressure on right front) "severe" turns, meaning lotsa tire scrub. Are those two turns producing more tire wear than the 8 righthanders, or are there other compelling reasons for your uneven wear like maybe camber or toe-out inadvertently slipped out several degrees?

AKKutz

Just took IR measurements after driving home from work. outside 101, middle 109 and inside 114. So, guessing an alignment issue? suggestions?

Hi Volts Z06

IR temp measurements are useless as well as tire temps taken during street driving. You need a real needle type pyrometer to get accurate readings at the track. Tire surfaces cool quickly and you need to read temps near the cords immediately after coming off track. (You really need someone ready to take them but you could do it yourself).

On your alignment specs...what is your definition of -.5 toe ? Are you saying you have 1/2" of toe out? Or are you giving mm measurements? Is that both front and rear or just front?

AKKutz

-.5mm as per DSC Sports rec settings.


I understand the IR vs Pyrometer. I thought that might give a slight indication of what is going on with the tire. Being hotter on the inside and seeing the excessive wear on the inside should be telling me something.... I just don't know enough yet what that might be.


I am coming out of the motorcycle world and having to learn a whole new set of information.

synner

Some tracks will wear one tire worse based upon track layout and the hardest turns. I'm not familiar with that track though. It doesn't hurt to do a side to side rotation midway through a weekend. This is assuming you don't have an alignment or pressure issue.

Tire temp from DD is useless, inside will be hotter since you have negative camber and drive straight.

mattastick

Everyone I know that has run at Putnam has always had left front wear issues. Some cars have gone through an entire left side or at least left front tires in a weekend.

Kubs

It looks like one side is toed out too much, but if that were the case the steering wheel would not be centered.

what is your cross caster (L to R difference)? Is anything else bent (control arm, tie rod, knuckle)?

AKKutz

This is right front. My last time at Putnam, I killed a set of oem tires on the inside all around. My left side tires look awesome as does the right rear, very happy with wear other than right front.


The track was resurface this past winter. I'm going to have to look at my alignment again this Sunday (only time I get to screw with car).


I was hoping it was a track issue, but not so sure now. I did hit a few of the curbs with that side of the car.

mikeCsix

Check out the website, there is some good info on suspension tuning and how to read tire temps:

http://parsbrorc.com/?page_id=268

IndyMikeC6

I can pretty much guarantee it's not a track issue. I was there last weekend and the previous one too. I didn't have any unusual tire wear issues. As you stated earlier, it's the left front that gets the abuse but after the resurfacing it's much much reduced from what was there before.

I would think alignment is the best place to start.

Mike

AKKutz

Thanks Mike that was the impute I was looking for. Since it was my only second event at Putnam in a car. As the first event almost corded the oem Michelins, I wasn't certain what to expect with the NT-01. But I was definitely shocked to see the sipes almost gone on the right front!


I was very happy with the wear on these tires on 3 of the 4 corners. I was running high 19s, low 20s for most the 2 days.


I found the toe out on the right front by a good 5mm negative. Not sure if that was enough to show this kind of wear, but everything else checked out. -2.0 camber, 7.5 caster.


I believe I was pitted close to your car.


Tony

IndyMikeC6

Cool. Stop by and say hello next time. I'll be there 10/13-14 and 10/28-29.

AKKutz

Who's events are these?