Here we go, back in the day, 64 light weight Dodge Hemi S/S four speed. The car had all the FX stuff on it. After awile the owner took off the rear springs, went to an auto and these where to stiff, asked me if I wanted them, I said no since I had a home made set of ladders. Anyway to the point, these springs where much thicker leafs, maybe 7/16 with five on one side and 5 1/2 on the other. He claimed they where made for the 4speed FX cars and would not wind up, I stood on them and they didn't bulge. He threw them on the pile with the stainless steel k-frame that was cracked. I found a set awile back and I'll use them on my 64 Savoy. Just thought I'd add that to the mix