I'm testing new tires that have a lot of rear traction on carpet, so I've already done everything I can to get the car to rotate. Loading the gear diff with 500K got the back end to slide just the right amount.
I'm either going to half fill the diff with 500K and store the diff upright between races or lightly coat the gears with Gravity 2 Million. Seems ridiculous, but with these tires, it's only .2 slower with a 25.5 than the track hot shot with a 21.5.