The PRO GM coil-over conversion spring is 4" inside diameter at the top so it will fit the stock upper spring pocket of 1970-81 Camaros and most 1973+ GM cars without modification; however it tapers to 2 1/2" i.d. on the bottom end so it can be used for ride height adjustment when using a coil-over front shock like the PRO C200. As GM did not design its front suspension to accept a true coil-over spring , this tapered coil gives better travel and makes installation a snap!

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