To me, running a musclecar on fifty year old springs makes no sense at all. Unless you are racing, small torsion bars do you no favors at all. I switched both of my cars over to the 1.03 performance bars and had no degradation of ride quality, but Man! what a difference in handling. Six of my friends were so impressed by the difference, that they changed over also and love them. Best $200 I ever spent. Biggest felt improvement for dollar spent.