I'm wondering how a spring acts when its compressed at diff levels. I think a full coilover setup is the best example.

Comparing the coilover when the spring is compressed to the max adjustment level (thread the perch all the way up), to when its compressed to the least adjustment (thread the perch all the way down), how does the spring differ in the two cases? Are the springrates different in the two situations? How would each ride in daily driving? Ignore the height and center of gravity issue, just focusing on the spring.

I don't own coilovers, but I noticed that when installing my prokit/bilstein HD's, that when threading the top strut nut, the more I tightened it, the more it would compress the spring before I put the assembly into the car. I'm wondering if Loosening the strut nut a bit would change the way the spring/suspension acts.

 

anyone have insight on how springs act when compressed?

 

I would imagine that each spring (brand/model) acts differently- the manufacturer would have this info- but they would not likely release it to you.

 

hmm dang...

btw, I was refering to a spring with evenly spaced out coils, not progressively spaced out coils. I forgot to mention that.

 

I don't think it makes a difference. A 400lb spring, for example, needs 400lbs to compress one inch. If it starts out compressed because it has weight on it already....it still needs 400lbs to compress another inch.

So whether you have a 3000lb or 2000lb car on the same springs, they should still compress the same amount when you get into it. Although the springs will seem softer on the heavier car because they have so much more weight to accelerate.

I don't really know if that's what you were looking for, and I am just spewing theory over here....


[Modified by Lsos, 1:06 AM 3/28/2002]

 

if they are progressive springs when you preload it (tightening down the nut) you are doing just that, pre loading it (but when you lower the car you preload it more, so the tightening of the nut doesnt affect the suspension). the rate will not be linear. if they are linear rate springs it will be the given spring rate no matter how much you pre load it. as for the height of spring on the pearch, it wont affect the rate.

 

Here's teh key to your question. You just have to consider that the spring doesn't get pre-loaded more or less with coilover height adjustment....if you only consider the spring.

The only other case you would have to consider is if you lowered so much that you were no longer relying on the springs for bearing corner load. In this situation, the simulated spring rate would be really high and approaching infinite b/c you're riding on the shock or bump stop.