Traction problems

Our '66 Cuda runs 10.68/123, with a pinion snubber/ radials/drag shocks. Start with the most economical change first. (pinion snubber) Then shocks. Do at least 3 runs for any one change to gather correct data. Then change tire pressure for 3 runs. Use a log book. Do not make the mistake of airing down radials if you encounter tire spin. Go the other way. Good luck