S550 Tire blowout/ripped question

[JAL racing]

Yesterday I went to the track and started with 28psi cold on MPS4S 305/30/19. After a session they were 32psi. Next session 32psi as well. Grip felt great.
On the way home at 65 mph I suddenly feel the car pulling left, then start to hop and I quickly stop on the shoulder. See photos of the tire.
I don't understand what happened. It is like the sidewalls were wearing from inside the tire until they were super thin and then completely ripped apart. Two part question:
1-What do you reckon likely caused that?
2-The remaining 3 tires have about 30% track life left. Would you replace just one, a pair, or all 4? I rotate after each track day but I reckon if I buy just one I could leave it on the front right corner (fastest wearing at my track) for the remainder of the set's life (about 4 days) and then replace all 4. WWYD?
Thanks!
*the last picture is one of the other 3 tires to give an idea of sidewall/tread outside wear. The inside sidewall/tread edge is better at 5/32nd.

 

[Mad Hatter]

Thats kind of scary.... Do you control the tire pressures using the cars tpms readings or with a pressure gauge? Had to ask..

I would not use them to be honest. And maybe send those pics to Michelin? That kind of complete failure could cause a catastrophic accident.

 

[JAL racing]

Thats kind of scary.... Do you control the tire pressures using the cars tpms readings or with a pressure gauge? Had to ask..

I use a pressure gauge. Every session. I never look at TPMS readings. This tire did not lose any air over the winter and was reading 32 psi before the drive home.

I would not use them to be honest. And maybe send those pics to Michelin? That kind of complete failure could cause a catastrophic accident.

I have to admit I am relieved it did not happen on track cornering at high speeds.
I am trying to gather info/advice here from you guys before I contact Michelin.

 

[blacksheep-1]

Looks like the tire may have rolled over enough to get cut by the bead of the wheel, or maybe just debris, was the track predominately in either right, or left hand turns, and was the tire pulled off the right or left wheel bead? lastly, what does Michelin recommend for pressures on those tires?

 

[JAL racing]

Looks like the tire may have rolled over enough to get cut by the bead of the wheel, or maybe just debris, was the track predominately in either right, or left hand turns, and was the tire pulled off the right or left wheel bead? lastly, what does Michelin recommend for pressures on those tires?

The track is right hand turn mostly and right side tires do wear faster there.
The tire pulled off the left (inside) wheel bead. Both sides are cut, but the outside only partially.
I cannot find minimum pressure recommendations from Michelin, but max is 50 PSI

 

[blacksheep-1]

Just a shot in the dark, but I'd bet they were underpressured, especially if the were cut on both beads

 

[DaveW]

Just a shot in the dark, but I'd bet they were underpressured, especially if the were cut on both beads

Yeah, this looks like it was run low on pressure.

DaveW

 

[JAL racing]

Yeah, this looks like it was run low on pressure.

DaveW

Thanks guys. I'll try my luck with Michelin and order 4 more. I can't believe I did not feel it go soft before it was too late.

 

[TMSBOSS]

I had the same, similar issue with a Cup 2. I picked up a screw and ruined the sideway in no time. I may have drove less than a mile at low speeds With low pressure. That was a $500.00 lesson learned in seconds.

 

[blacksheep-1]

Thanks guys. I'll try my luck with Michelin and order 4 more. I can't believe I did not feel it go soft before it was too late.

Might try them thar Goodyears we used at Daytona

 

[JAL racing]

Might try them thar Goodyears we used at Daytona

I'm not 3R driver caliber yet. I'm still a beginner and I'm broke so longevity > performance. I wouldn't be able to extract the additional performance from the better tires.

 

[JAL racing]

I had the same, similar issue with a Cup 2. I picked up a screw and ruined the sideway in no time. I may have drove less than a mile at low speeds With low pressure. That was a $500.00 lesson learned in seconds.

Did you end up replacing just one tire?

 

[blacksheep-1]

I'm not 3R driver caliber yet. I'm still a beginner and I'm broke so longevity > performance. I wouldn't be able to extract the additional performance from the better tires.

not 3R, just "3". we ran them for about 12 hours straight at Daytona and the lap times never fell off, they were amazing.
You may want to look at all 4tires for damage if you ran them all that low.

 

[TMSBOSS]

Did you end up replacing just one tire?

Since the car and tires were new, yes just one tire. Under 1500 miles of car and tires.
I pulled all 4 off soon after. GT350R carbon fiber wheels. I learned that it did not take long to loose a tire. A mile or two more and I may have lost a wheel too. I have 3 sets of Apex wheels I run now.

 

[JAL racing]

Aftermath: Michelin apologized and will cover 100% of the cost for a new tire.
My personal experience with "warranties" usually ends up with me being told "Sorry it's not covered". I was surprised and pleased I did not have to argue or make complicated representations.
I called Michelin, they told me to get the tire checked out at one of their dealers. The dealer took a look, tread depth, called Michelin and said they were sorry and this should never happen and they will provide me with a new tire free of charge.
I couldn't believe it but hey, I'll take it!

Blacksheep- yes I intend to keep the other 3 as spares, but I will inspect them carefully for similar inside wear. And I will try the supercar 3 after this next set!