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This is the right front tire off of one of the mustangs that ran at Homestead in T2. We had 3 cars in that class, with marginally different set ups, the biggest being types of coil over shocks, in any case, the SCCA rules package for T2 now requires the cars to run 275x18 tires, limited to 3 degrees of camber and a smaller restrictor. This had the following effect, the smaller tire, of course took a bigger beating than the 295 or 305 tires used prior, secondly, the lack of camber also created an adverse situation, even the smaller restrictor conspired against us as now the drivers could run flat out through the banking, when before, with a larger restrictor they had to let off in the bank, now they could drive flat through the corner.
Two other items contributed to this, 1, is the drivers were using a lower line through the corner, moving up the track greatly increased tire longevity, and 2, it rained the night before creating a "green" track, increasing tire wear.
All of these led to an increase in tire wear beyond acceptable limits, to combat this, pressure was increased slightly, (more on this later). The driver's line had to be changed, and we scuffed the right side tires in on the left side of the car in the qualifying session (this tire was scuffed on the LR, then shifted to the RF for the race).
This tire basically lasted about 26 laps.
While I'm unable to publish tire pressures, this particular car ran about 3 psi higher cold pressures than the other 2, while a greater increase in tire pressure was recommended by Hoosier, there is a serious caveat there. If you increase pressure too much, the tire slides, more steering input, creating heat, creating pressure and then it will get out of hand, degrading the handling of the car, and possibly creating an even more dangerous tire situation. I had been mapping tire/temps for 2 days prior to this in order to keep all the cars within our acceptable hot range, I "fudged" this pressure on the right side to try and extend tire life and still stay within our performance limits. it looks like I guessed just about right.
Whenever you run banking, don't be afraid to run extra camber..extra, not excessive, and monitor across the tread tire temperatures for any clues to tire degradation, lastly try and scuff the tires on the right side of the car (banked to the left), monitor tire wear, run a higher line and inspect the tires often. "Mapping" the pressure and tire temperatures is also the best idea to stay ahead of problems.
Two other items contributed to this, 1, is the drivers were using a lower line through the corner, moving up the track greatly increased tire longevity, and 2, it rained the night before creating a "green" track, increasing tire wear.
All of these led to an increase in tire wear beyond acceptable limits, to combat this, pressure was increased slightly, (more on this later). The driver's line had to be changed, and we scuffed the right side tires in on the left side of the car in the qualifying session (this tire was scuffed on the LR, then shifted to the RF for the race).
This tire basically lasted about 26 laps.
While I'm unable to publish tire pressures, this particular car ran about 3 psi higher cold pressures than the other 2, while a greater increase in tire pressure was recommended by Hoosier, there is a serious caveat there. If you increase pressure too much, the tire slides, more steering input, creating heat, creating pressure and then it will get out of hand, degrading the handling of the car, and possibly creating an even more dangerous tire situation. I had been mapping tire/temps for 2 days prior to this in order to keep all the cars within our acceptable hot range, I "fudged" this pressure on the right side to try and extend tire life and still stay within our performance limits. it looks like I guessed just about right.
Whenever you run banking, don't be afraid to run extra camber..extra, not excessive, and monitor across the tread tire temperatures for any clues to tire degradation, lastly try and scuff the tires on the right side of the car (banked to the left), monitor tire wear, run a higher line and inspect the tires often. "Mapping" the pressure and tire temperatures is also the best idea to stay ahead of problems.
