[travislambert]

As part of my normal track prep I was going over everything on my car and noticed my basically new front tires were starting to cord.

These tires were $1,996.22 from Tire Rack, and after about 2 hours of track time both fronts were starting to cord. The rears aren't much better. I would estimate within another session or two the rears will also be corded.

I'm beyond frustrated because I followed Hoosier's guide the best I possibly could. I paid Tire Rack to heat cycle them, I had the car aligned before installation with -2.9 degrees of camber up front (maxed), and I targeted 41-42 psi hot.

I was getting 5-6 track days out of the GoodYear Supercar 3s so I was expecting at least 4 track days from the R7s.

The worst part is, I have a 2-day track event this coming weekend and only have street tires to run. Not sure I want another set of R7s a this point, but even if I did there wouldn't be time to get them.

Has anyone else experienced this? Did I do something wrong?

[RUQWIKR]

I don't know if it is linear with Hoosier's 040 Tread Wear rating, but, I am getting about half the life out of the G3R's (100TW) vs. the G3's (220TW) with similar alignment specs. This is also rotating side to side on 2-day events to even out the sidewalls. I have gotten better life after flipping the tires on the rims with no issues, but DO NOT drive in the rain with them flipped as the sipes will be facing the wrong way. The Hoosier R7's can be flipped without issue as they are non-directional. Any of these will suck in the rain regardless, and as you know, the Hoosiers are not legal for highway use based on the competition only writing on the sidewall.

Your typcial track day is how many heat cycles and hot track time?

[travislambert]

Originally Posted by RUQWIKR

I don't know if it is linear with Hoosier's 040 Tread Wear rating, but, I am getting about half the life out of the G3R's (100TW) vs. the G3's (220TW) with similar alignment specs. This is also rotating side to side on 2-day events to even out the sidewalls. I have gotten better life after flipping the tires on the rims with no issues, but DO NOT drive in the rain with them flipped as the sipes will be facing the wrong way. The Hoosier R7's can be flipped without issue as they are non-directional. Any of these will suck in the rain regardless, and as you know, the Hoosiers are not legal for highway use based on the competition only writing on the sidewall.

Your typcial track day is how many heat cycles and hot track time?

These tires were used for 3 sessions during a TNiA event, and then 4 sessions a couple weeks later(Technically 5, but 1 session was basically parade laps.) The sessions ranged from 15 to 20 minutes each. I didn't even finish the second track day before cording these. I left with a few sessions remaining due to rain.

[ninetres]

Pressure seems a little high. Any chance you were taking tire temps with a needle across the tire face while HOT?

Maybe too much camber for your driving style as well.

[travislambert]

Originally Posted by ninetres

Pressure seems a little high. Any chance you were taking tire temps with a needle across the tire face while HOT?

Maybe too much camber for your driving style as well.

It's high for most tires, but that's the pressure that Hoosier recomends and where the tires seem to grip.

Unfortunately I wasn't taking temps. I need to get a gauge.

If anything it's not enough negative camber. The tires were worn on the outer edge. Hoosier recomends -3.0 up front if I remember correctly. -2.9 was all I could get (I modified my struts to go beyond -2.2).

Any way you slice it though, that's $1,000/hr for tires... I was expecting a little more value I guess.

[travislambert]

The video below shows one of the laps on the tires. The grip is amazing. I just wish they would last a little longer.

[ninetres]

Originally Posted by travislambert

It's high for most tires, but that's the pressure that Hoosier recomends and where the tires seem to grip.

Unfortunately I wasn't taking temps. I need to get a gauge.

If anything it's not enough negative camber. The tires were worn on the outer edge. Hoosier recomends -3.0 up front if I remember correctly. -2.9 was all I could get (I modified my struts to go beyond -2.2).

Any way you slice it though, that's $1,000/hr for tires... I was expecting a little more value I guess.

Oh wow I figured that was the inside (or I misread). Yea more camber needed maybe. Hoosiers recommendations are just general suggestions....not gospel.

I’ll try to watch you video tomorrow. Maybe see if I can tell if the car looks to be doing something that would cause that (IMO of course).

[travislambert]

I talked to Tire Rack this morning mainly just to let them know what had happened. They asked me to send pictures.

There's no warranty with the tires, so I doubt they do anything, but who knows. I expect they'll tell me I need more negative camber and need to run higher pressures. Maybe then I'll get 2 full track days out of 'em...

Unless they tell me the tires in that batch were defective, I doubt I run R7s again. I simply can't afford $1,000 a day for tires.

I'll keep you guys posted if/when I hear back.

[rotis]

It's because you need more camber, and less dynamic camber loss due to body roll. (ie. you need significantly more roll stiffness)

You have a lot of tread left across the face of the tire.

[travislambert]

Originally Posted by rotis

It's because you need more camber, and less dynamic camber loss due to body roll. (ie. you need significantly more roll stiffness)

You have a lot of tread left across the face of the tire.

I totally agree. Over the winter I'll be making some changes to the suspension.

I'm still a little disappointed in the tire life though. Not everyone has a perfectly tuned race suspension, so I'd expect these tires to last at least a few track days on a car like a ZL1. For a 20" tire, Hoosier has to know these are being ran as track day tires on street cars.

[Move_Over]

Wowza, my R7's on my E46 lasted about 4 weekends. Granted, about 600 less lbs, and 200 HP less, but still.

What suspension changes are you going to be making? I wish chevy performance would come out with a stiffer spring for the 1LE mag shocks. Would greatly reduce roll.

[travislambert]

Originally Posted by Move_Over

Wowza, my R7's on my E46 lasted about 4 weekends. Granted, about 600 less lbs, and 200 HP less, but still.

What suspension changes are you going to be making? I wish chevy performance would come out with a stiffer spring for the 1LE mag shocks. Would greatly reduce roll.

I have the solid cradle bushings but haven't installed them yet. I was thinking about ZL1 1LE DSSVs and sway bars in addition to the bushings. The 1LE struts would make it much easier to get the camber I want/need.

Yeah, not sure why there aren't more options for us mag ride folks. I was thinking at least offer a tune or dummy plugs so we can install the DSSVs with all GM parts.

[travislambert]

Here's the response from Tire Rack:

When we address tire/wear questions stemming from competition use, we often use the statement that tires follow the equation Work = Heat = Wear. If we see where one occurs, we know the others are in the same location. This is another example illustrating this simple truth.

The photos show tires with wear that is heavily biased on the outside shoulder. When turning, the tires experience very high lateral forces, and this force is directed from the outside in, with the leading edge (outside) experiencing the most force. If the vehicle has a completely stock suspension, it was still designed from the outset to be a street-driven vehicle, and the factory suspension doesn’t have the adjustability to allow the amount of negative camber typically needed on the track.

From the way the tires are wearing, we can see that most of the cornering is being done on the outside shoulder, which is an indicator that more static negative camber is needed. The customer mentioned that the front is maxed out at -2.9 degrees, but looking at these tires tells us that they (the tires) really want about 4-5 degrees of negative camber on this vehicle to plant the footprint in corners better and wear out more evenly. The vehicle body roll through a corner leans the tire outward, effectively increasing the camber (making it more positive). The fact that the customer’s previous Goodyear tires wore evenly and the new Hoosiers corded in the shoulder so quickly brings up the fact that when ultimate grip levels are increased, the car will experience even more body roll in hard cornering, further shifting the weight down into that outer shoulder and rolling it over even harder. More grip means higher cornering g-forces, and therefore more body roll as the vehicle turns. Add to this the fact that more grip also means more speed, which in turn results in more body roll, and the situation is compounded.

We actually have an informative tech article that discusses this situation on our website located here: https://www.tirerack.com/tires/tiret...jsp?techid=161

I would recommend a bit higher inflation pressures to help combat the rollover and help move the work back up off of the shoulder and into the tread area to help the tires wear more evenly. It was good that the customer thought to rotate the tires to help spread out the wear, and that can actually be taken one step further by dismounting the tires from the wheels and having them flipped so the inboard shoulder faces out, essentially giving you a fresh start on the outboard shoulders if camber is unable to be adjusted any more negative. In case the customer is unaware, the tires have molded pin holes near the shoulders for judging remaining tread depth. The bottom of these holes is only a skim coat of rubber above the body cords, so when those holes are getting shallow on one shoulder, the tire is getting close to worn through in the shoulder. These holes are pointed out in the attached photo of a new tire of the same type as the customer had on the front of his vehicle.

In the driver + vehicle + equipment/setup equation, any time one of the variables changes, the outcome will change as well. The final adjustment to make is to driving style. In order to conserve the tires, smaller steering inputs with less slip angle and less power-on oversteer while exiting turns would be very beneficial. This will result in less sliding and help conserve those shoulders.

[travislambert]

Other than increasing my tire pressures a little, there's not much more I can do without changing out the entire suspension of my car. I don't think there's any change I could easily make to meaningfully extend the tire life to a reasonable level. I would have been happy if I could get a couple weekends out of them, but not having enough tire life for a single weekend isn't going to work, especially considering the cost.

I assumed these tires were made for casual track-day enthusiasts like myself because I'm not aware of any purpose-built track cars running 20" wheels. People in the market for tires like these are likely pushing the limits of their street tires. I suspect that since most street cars aren't adjustable to the camber level needed to compensate for the increase grip and dynamic camber loss, my experience will be common.