thefleshrocket
Seasoned Member
I did a track day (four 20-minute sessions) with my 5BW with the street alignment, at WWTR near St. Louis, back in September 2023. It chewed up the outside edge of the passenger side front tire, so much so that I replaced it after the track day. I then had the track alignment installed. I did another four 20-minute-sessions track day at WWTR, and then I did a "run as much as you want" track day at NCM, where I probably did about 110-120 minutes of track time. In between there, the 5BW had its winter wheels with all-seasons installed, for, I would guess, about 2000 miles. The 5BW now has about 7400 miles on it, and the inside edge of the passenger-side front tire is slightly corded (one tiny spot poking through) and the driver's side is barely better. But the tread not near the edges of the tires has plenty of meat left. The rears look okay, well worn consistently acorss the entire tread. Tires are the factory PS4S.
It's my understanding that toe causes inside edge tire wear, not camber, but the track alignment that I had my alignment guy set is as follows, which is only 0.1 degree total toe:
Front: -2.5 deg camber, 0.1 deg total toe
Rear: -1.5 deg camber, 0.1 deg total toe
Now maybe it was tire pressures. At WWTR, I was in the upper 20s (like 28 or 29) when going out onto the track, and into the mid-upper 30s (like 36-37) by the end of the session. So hot was where it was supposed to be, but cold was a little low. Not sure how else to handle that, though--when the tires are picking up nearly 10 PSI after a 20-minute session. I don't have any in-car video from NCM (so I can see the gauge cluster) so I don't recall what tire pressures I was running there, but I assume comparable to WWTR.
The street alignment is clearly not optimal for outer-edge tire life at the track, but the track alignment apparently isn't compatible with the inner edge for street use. I can't justify a $100 alignment before and after each track day, so I'm hoping that there's a mid-way compromise in front-end alignment. There's not a whole lot of change I can make with the toe, since the track alignment is only 0.1 degree total toe. The 2.5 degrees of negative camber is pretty aggressive, but, again, I thought that it's toe that kills tires. Maybe dial back front negative camber to 1.5 degrees, to match the rear?
It's my understanding that toe causes inside edge tire wear, not camber, but the track alignment that I had my alignment guy set is as follows, which is only 0.1 degree total toe:
Front: -2.5 deg camber, 0.1 deg total toe
Rear: -1.5 deg camber, 0.1 deg total toe
Now maybe it was tire pressures. At WWTR, I was in the upper 20s (like 28 or 29) when going out onto the track, and into the mid-upper 30s (like 36-37) by the end of the session. So hot was where it was supposed to be, but cold was a little low. Not sure how else to handle that, though--when the tires are picking up nearly 10 PSI after a 20-minute session. I don't have any in-car video from NCM (so I can see the gauge cluster) so I don't recall what tire pressures I was running there, but I assume comparable to WWTR.
The street alignment is clearly not optimal for outer-edge tire life at the track, but the track alignment apparently isn't compatible with the inner edge for street use. I can't justify a $100 alignment before and after each track day, so I'm hoping that there's a mid-way compromise in front-end alignment. There's not a whole lot of change I can make with the toe, since the track alignment is only 0.1 degree total toe. The 2.5 degrees of negative camber is pretty aggressive, but, again, I thought that it's toe that kills tires. Maybe dial back front negative camber to 1.5 degrees, to match the rear?
