64 rear leaf spring

[Rick N.]

Re: Free arch for non-GM springs

Thanks to Gary and all who provided good info. Rick

[John H.]

Re: 64 rear leaf spring

Rick -

"D" height is measured by taking the dimension from the centerline of both the inner and outer camber strut rod bushing bolts to the ground and subtracting the outer dimension from the inner dimension; for a '64, the result should be 3-3/8".

Spring rates are specified by GM at their design load (the "load rate"); all midyear standard 9-leaf rear spring rates are identical - 140 pounds per inch at 1360# load, applied at the link bolt hole.

[Rick N.]

Re: 64 rear leaf spring

John, thanks for the numbers. I did a quick of my spring and its free arch height was approximately 10". There's a number stamped on the bottom, 21-307. I wonder who made this spring set. Hopefully, my car will be put back together in the next couple weeks, and I can check/set the ride height using your data. Rick

[Larry L.]

Re: 64 rear leaf spring

I did a tech article on determining the correct ride heigh and what demensions,and load that you have to give a spring shop to re-arch your spring. You have to do this to all NOS Chevrolet springs so you ride height is correct.

Look at ncrs.org/mvc and review the quarterly Vette-Gazette articles. It gives you two ways to get the correct numbers.

Once the spring shop is done with the spring, dissemble it and lube the liners with silicone grease or you will get a choppy ride.

Works every time.