PS2 tire wear

[wastntim]

At IL VCA's last track day, the 2nd of the year, one of the members was looking at his track tires, and realized that his cords were showing on his PS2's. One might not be that upset thinking that he had used these tires for a season, but in fact, he had just purchased them at the beginning of the year and had used them ONLY for the clubs 2 trackdays! Basically he corded brand new ps2's after total cumulative track time of three hours. He was taking the situatoin far better than I would have, considering the cost of ps2's.

Having just mounted ps2's on my track rims and used them for two days, I have also noted significant wear, especially on the outside edge of all of the tires. This is the same place the other members tires were showing cords. I ran all of last season on a set of kuhmo's without a single problem, other than a good amount of rubber on the car.

My question is to those of you tracking their cars on ps2's. Have you experienced this type of rapid tire wear? How many events have you been able to get out of a set of tires? What tire pressures are you starting off cold typically?

[rcl4668]

I've just done an autocross school on the 08 but have a series of HPDE events planned in the next few weeks at PIR here in Oregon. I plan to start with 30 psi rear and 34 psi front cold and adjust accordingly after each session.

I guess one (expensive) alternative is to buy an extra set of rims and tires with a set of PS2s (or DOT competition rubber) for use just on track days.

/Rich

[mjorgensen]

I would suggest that the pressures were to low and the sidewall was taking all the load instead of the tread. The cold pressures for the street are way to low to run out on the track and the non runflats will need more pressure to support the car under load.

[VIPER GTSR 91]

No problems on my ps2s wth 2 track events. Starting cold 31 psi.

[wastntim]

Believe it or not, the guy with the tire problems was starting at 34 cold in the fronts and 30 in the rears.

I actually started at 28 cold front 27 cold rear. I then even lowered the tires more based upon my pyrometer readings. Basically, I was looking for a nice even range of temperatures across the tire. I even lowered the pressure more as the day went on and the tires and track warmed more. As the day heated up, I started to see temperatures in the center of the tire rising above the outsides, which, to me, indicated the pressures were to high. The one thing I felt was that I could use some more negative camber. However, I felt like the tires pressures were good based upon my pyrometer readings.

[rcl4668]

Originally Posted by mjorgensen

I would suggest that the pressures were to low and the sidewall was taking all the load instead of the tread. The cold pressures for the street are way to low to run out on the track and the non runflats will need more pressure to support the car under load.

Mark --

Have you had the chance to run 2008 Viper or other Vipers with the PS2s at the track? What would you recommened as good cold starting pressures for a typical 4-5 session HPDE event (each session lasting 15-20 minutes)? I remember a year or two ago I asked either you or Bill P about this and the recommendation for my 2006 with the runflats was to start at 30 psi rear and 34 psi front cold. Thanks for your input and advice.

/Rich

[VIPERUSH]

Originally Posted by wastntim

At IL VCA's last track day, the 2nd of the year, one of the members was looking at his track tires, and realized that his cords were showing on his PS2's. One might not be that upset thinking that he had used these tires for a season, but in fact, he had just purchased them at the beginning of the year and had used them ONLY for the clubs 2 trackdays! Basically he corded brand new ps2's after total cumulative track time of three hours. He was taking the situatoin far better than I would have, considering the cost of ps2's.

Having just mounted ps2's on my track rims and used them for two days, I have also noted significant wear, especially on the outside edge of all of the tires. This is the same place the other members tires were showing cords. I ran all of last season on a set of kuhmo's without a single problem, other than a good amount of rubber on the car.

My question is to those of you tracking their cars on ps2's. Have you experienced this type of rapid tire wear? How many events have you been able to get out of a set of tires? What tire pressures are you starting off cold typically?

Hi, I am concerned about your observation on PS2's rapid tire ware. I am in the process of trying to find a alternative to my worned out run flats and everybody seem to suggest I should go with PS2's (see Any alternative to Michelin Tire.)

Would you recommend PS2's for regular road driving?
Any concerns about using pressure foam kit in case of a flat tire i.e. Uneven balance in case too much foam hardens in one spot inside the tire?
Thanks Richard

[wastntim]

Originally Posted by VIPERUSH

Hi, I am concerned about your observation on PS2's rapid tire ware. I am in the process of trying to find a alternative to my worned out run flats and everybody seem to suggest I should go with PS2's (see Any alternative to Michelin Tire.)

Would you recommend PS2's for regular road driving?
Any concerns about using pressure foam kit in case of a flat tire i.e. Uneven balance in case too much foam hardens in one spot inside the tire?
Thanks Richard

At the beginning of the year I actually purchased two sets of ps2's from JonB. One for the street and one for the track. I began using the street set first and was totally impressed with them. They were far superior to the hockey puck like tires I replaced. They really feel like they have much better grip. On that set my wear seems fine at this time, and nothing like my track tires. Even though I have a couple thousand miles on my street tires, they look like new compared to the track tires. The only time I haven't liked them was when I got caught in a flash flood, they were darty at best, but that might be more because I went up to 295's on the front.

As for the foam, once it goes in, I wouldn't trust the tire. IMHO foam gets you home but shouldn't be relied upon for any period of time. You might then try to patch the tire, but based upon the speeds of a viper, I wouldn't want to be driving on a patch.

[Viperless]

Originally Posted by VIPER GTSR 91

No problems on my ps2s wth 2 track events. Starting cold 31 psi.

Ditto.

Sport shims removed, 295's on the front and only the outer 50% of the tread shows wear. More neg. camber??

[mjorgensen]

The factory did tweak the settings for the new tire package on the 08' cars so the requirement of more negative camber could be needed on the Gen3 cars. We have set up a few cars for the "track" with the Motons and usually go with 1.3-1.5 degrees negative in the front and .5-.8 negative in the rear. I have not had any complaints thus far from our customers about were on the track or the street with these settings. FWIW

[wastntim]

I'm curious, has anyone else running ps2's ever tested their tires with a pyrometer while running on the track?

[mjorgensen]

Testing pressures at the track require a second person doing it to be sure because they start to equalize temps so fast across the tire so you should duck into the hot pits and start with the tires that were used most during the last corner taken.

I know most of you know this stuff but feel the need to tell the less experienced track junkies the drill.

[1fastviper]

I just have a few hundred miles on my ps2s.No track use.All street.I have not had any wear problems yet..As far as quality and performance goes you cant beat them..