If radials work on a high power trans brake car, why not a stick? The car in question has extension to loose. It slams the housing out, kills the tire and then bounces the rim back off the pavement. A radial requires different valving than a slick. I'd tighten the rear and test again. If that doesn't get it remove hit with the cal track. Still no good? May need a better shock, test and find out.
Doug