I want to replace the springs in the front of my 68 chevelle. ITs a 2dr coupe with a 355 and no a/c and a auto. I took the old ones out and the pass side had 2 blocks in it and i'm assuming there original since it looks like the ball joints are. I want the same ride height as before and need to figure which stock spring to get but i don't understand the meanings. I measured my current springs and there 18in tall out of the car. I have the cc501 springs in the back and i just don't want new springs that will raise the front higher then the back. The load rate say its 2000lbs what does that mean. Do i want a lower one for the small block?

thanks,

Spring load, is the ammount of weight it takes to compress to a certain height. (pounds)

Spring rate is the ammount of weight it takes to compress the spring 1 inch. (pounds per inch)

Example: imagine a car that is leaning very bad, the springs are compressed with 1000 pounds on each spring to 14" on one side, and 13" on the other side, both can have the same rate (example = 250lbs) which means both are compressed 4". One is 17" free height, the other is 18"

If you want them both at 13", the one that is at 13" has a load of 1000 pounds (at 13") The one at 14" has a load of 1250 pounds (at 13")

The spring itself will have two specifications:
A) the spring rate in lbs/inch
B) free length

Your car will have a certain amount of weight on each wheel. After correcting for leverage affects, this will be the load rate. In a Chevelle the spring is about halfway up the LCA so it sees 2x the wheel load. So if there is 1000 lbs on the tire, there is about 2000 lb load rate on the spring.

If you want to control the ride height you need to figure out the fitted or loaded length. This will be the free length minus load rate / spring rate. So if we have a 500 lb/in spring it will compress 4" at a 2000 lb load (using our numbers from above). Thus if fitted length at proper ride height is 8" we would need a spring that is 12" free length.

Hope that explains what is going on.

Of course you *did* measure the fitted length of the springs before you removed them, right? And obviously you know exactly what weight is on every wheel on your car too. :)

So for a small block i don't want a spring with to much of a spring rate or its going to sit to high?