Norm, clean threads and flanges, tapered wells in the wheels clean, always use a torque wrench?
Always, and I torque the lug nuts in two, sometimes three stages (70-100 or 60-80-100 depending on how I feel at the moment).
Very interesting. Do you change wheels very often?
Quite a lot, I guess. Swapping among the track set, the "3-season" set, the original all-seasons (that I've quit using entirely the past 3 or 4 years), and a few extra times for the times I've bled brakes or changed pads and/or rotors has put them through more than a few torque cycles.
This!
Shearing wheel studs is on my list of things that I hope I never encounter at the track (well, anywhere really, but especially at the track).
Actually, where and when it happened was probably as good a time and place as it could have possibly been. Other than needing to MacGyver a solution by stealing a couple of right front studs so it would roll up onto the flatbed, anyway. I did have a lot of help from a couple of guys I'd met at the hotel a couple of days before.
Got some new studs at an Autozone located walking distance from the hotel, heat-stressed myself getting the right side done so my son picked up the work on the left side.
These OE studs lived for around 45,000 miles, 2000 or so of those happening at 16 track days over the past 4 years.
I'd run 3.5 sessions in HOD's B-group and had been OK'ed to run in C, which I chose to do for half a dozen laps or so, as much for an easy introduction into the faster group as anything. That half lap in B was caused by a coolant spill.
Look at how the curves suddenly deviate at around 1:11 or so where the vertical cursor is set - the laps aren't atrociously inconsistent up to that point even though it was at the very end of a 2-day. Pure and simple, 1.2g lateral there was one time too many. Going back to the idea of it being fortunate timing etc., I have to wonder how much longer it'd have held up in my street driving, and I know I was extremely fortunate that it didn't happen under braking for T1 (120+ down to 70-ish). As the speed curve that goes to zero suggests, it was a rather uneventful slide to a stop, missing a drainage grate by maybe a car width.
Session 1 as background info. I really wish I'd got video of the incident.
https://i.ytimg.com/vi/L2noaEvV7uw/mqdefault.jpg
Today's update - I'm sure it's one of the "borrowed" studs, but I now have one LF lug nut that will not take full torque. So the car will sit until I get the new parts - all $$$$.¢¢ worth - installed. Gonna squeeze a little more suspension modding out of it as I go. Wife doesn't mind even this part, so yeah, I guess I'm lucky there too.
Norm