[chiphead]

I've got a '67 Lemans with TH350. Same rear as yours, but 3.23s and a powertrax locker. My 400 making about 360 HP twisted the stock pass side axle on street tires. After about 4 passes I noticed the rear end was making noise. Likely the powertrax made the situation worse, but I dumped that whole setup for a Ford 9. I agree on running the street tires, better to spin the tires than dead hook on slicks and break stuff. IF you think you can walk it out on the slicks, you can try it, but it'd be hard on the clutch disc. The tracks I used to go to never checked anything. I was running ET streets and nobody ever looked under the car.