Spring compression rate -1967

[Keith B.]

I need to know what the standard spring rate is (lbs. per inch) for a small block spring (1967). This is for the 12 coil spring.

Thanks

Keith

[Duke W.]

Re: Spring compression rate -1967

It's a variable rate spring. The only data I have for the C2 variable rate springs used from '64-'67 is for the '65 396. The front spring rate is 207 - 380 pounds per inch versus a constant rate of 260 pounds per inch for the '63 base springs.

These compute to wheel rates of 67-123 pounds per inch for the variable rate spring and 84 for the linear rate '63 springs.

Rear spring rates are 140-168 and 162 pounds per inch respectively. I don't have computed wheel rates for these spring rates, but they would be a bit less because of the leverage ratio.

This data is from Ludvisgen's book, and as I said the variable rates are for the '63 396. The '67 SB might be a little softer.

By comparison the linear spring rates for the F-40/41 suspension are 550/305 pounds per inch, which is about double the fixed rate springs used in '63 and about double the average rate of the base suspension variable rate springs.

Duke

[John H.]

Re: Spring compression rate -1967

Keith -

The 3851100 '67 SB front spring rate is 195#/inch, and 80#/inch at the wheel, at its design working height (9.98" @ 1340# load).