Corrective coil springs?

[wirelessF]

So I've noticed a 1" front driver side sag on the 2WD 2002 Silverado (coil spring front). There are two spring replacement options, for driver side height correction and regular pair. What should I get? Any reason why there are corrective versions?

I'm guessing that with the corrective coil springs the driver side will level out when it's loaded but will make the pass. side look lower when unloaded.

 

[eljefino]

I'm guessing to overshoot the stock height so when they sag over time you'll be happy.

 

[ChrisW]

It's been my understanding that springs, coil ones, shouldn't sag over time? That it's bushings and rubber parts that 'sag' over time [if you think about cars that get lowered, you're always told to wait until it settles to get an alignment; if you have zero-deflection bushings or mounts like delrin or spherical bearings whatnot, you wouldn't necessarily have to wait for it to settle]. I guess that would depend on what type of spring, how the spring was made, whether it was cold formed, hot formed, etc...what kind of metallurgy it uses. I say all this because I remember reading from a well respected honda-tech racer who had close ties with Eibach springs, he mentioned about this, and also from an old-timer locally here who used to make his own anti-sway/roll bars; I believe he hot-formed his as his thinking was that the metal is flxed when cold, what's going to prevent that constant torquing from deforming the bar. Someone can probably shed more scientific info on this and certainly correct me if I'm wrong. Maybe I should take a strength of materials course; my father said that was a fun class in high-school [back in the day of course].

 

[zzyzzx]

Do you have a manufacturer's name and part number and what does their literature say about the product?