I was at CMP this past weekend with THSSC and Triangle Z. Great bunch of guys. A very fun event. The car was doing OK considering the hot greasy track. I was on track at speed and heard a pop and then a big puff of smoke from the right rear. The smoke was cause by the rear tire hitting the fiberglass flair. Great, more body work.
I do inspect the car on a lift and I inspect the control arm welds with light and magnification. I don't think I would have caught this even with disassenbly and inspection.
The rear inboard attachment point broken
http://forums.hybridz.org/uploads/1276690252/med_gallery_787_732_2565090.jpg
http://forums.hybridz.org/uploads/1276690252/med_gallery_787_732_1654562.jpg
And this is what will replace the rear control arms.
http://forums.hybridz.org/uploads/1276690252/med_gallery_787_732_589558.jpg