I am thinking about installing a pair of progressive rate springs on the front end of my 1972 164. I want to maintain the current ride height....which is original to the car. Has anyone done this? What springs did you use? Are the springs on a 140 the same as those on a 164 in diameter, length and stiffness. Even if they are the same dimensions, I may want a stiffer spring than the 140 because the 164 is heavier in front and that would maintain correct ride height. All suggestions, insight cheerfully accepted.

Hello Ira!!!
I do know that '75 164's had unique, stiffer springs than all
previous years. This is the set you should probably go with
if you try the experiment at all.
Gary in Arizona--with two 164's.

I think the front springs are very different than
the 140 springs. If you find anyone who can supply
progressive springs for the 164, I'd like to buy a
set as well, unless they are crazy expensive.

I put rear springs from a 242 turbo in my 164 and
that cured my (car's) saggy ass. The fronts are
not compatible, though.
chris

John Parker at Vintage Performance Developments has progressive rate springs for the 140 in two spring rates. If the spring length and coil diameter of these were the same as the spring currently in the 164 I would be willing to test it out. He told me he has never tried either of his progressives on a 164 so cant tell whether or not the ride height would be same as or different from the existing. So the key issue is whether or not the coil diameter and length would allow me to fit them in the 164. Any insight, suggestions???????

The thing necessary in any spring to get you the same ride height as originally is that the replacement spring exerts the same force on the suspension as did the original spring when the suspension is at the original ride height. For coil springs, if the replacement spring is a little too short when it exerts this same force, it can be shimmed at its ends. If it is a little too long, it needs to be cut shorter, which however gives it a proportionally stiffer behavior in use. The unloaded (or "free") length of a spring is no direct indication of its usefulness.

These principles, and the formulas for calculating a spring's properties and how the spring's leverage on suspension arms is accounted for, are expertly presented in a book by Fred Puhn called "How To Make Your Car Handle", that has been in print for many years, by HP Books and its successor, and is sold in speed shops and bookstores that have a good automotive section. There's no good substitute for accurate measurements and doing the math, then fine tuning the setup once it's assembled. Also, shock absorber stiffness needs to keep pace with changes in spring stiffness.

Charles Greenlaw, Sacramento Calif.

I wouldn't bet the farm on this. The nose of the 164 supports 1.5x the engine weight. I'm thinking 140 springs would be a bad thing.

Maybe find some 140 stock-type junk springs, fit them, and see what the nose does.

The old R-sprt catalog offered springs something like what you are looking for. They did state that they would share between 140 and 160 with a 50mm lower ride height in the 6 cyl car.
They are of course nla, but the ones from John P sound good.