I destroyed an 8 1/4 with a small cam in a 318 with an auto trans in about 6 months in my 35 Dodge street rod. The 3:55 Sure Grip, 235*60*15 tires, and traction proved too much for the carrier bearing bolts. In low gear, standing start, wot, and BOOM!

The 8 1/4 came out of a 73 340 auto Duster with 55K miles on it that I converted to a dirt track car. We had an 8 3/4 set up for racing we used in the Duster. Gene