[Hiboost]

Originally Posted by Tractionlimit

This may be a dumb question, but why is every coilover at least twice the stock spring rate? Are we comparing apples to apples when looking at the spring rate of a traditional spring kit vs. coilover? Do coilovers ride that much more harshly, and would something like Eibach be a realistic option for the track?

Thanks.

The spring rates are measured the same way on Lowering Springs as well as Coilovers. The biggest difference is that Lowering Springs are limited by what spring rates they can use if they are going to be used properly with the stock OEM shocks. Typically you will only see 10-30% increased spring rates and often progressive rate springs will minimize the impact on how much of that you feel in daily driving. If the spring rates are too high they will wear out the shock faster and could actually hurt the handling of the car if the shocks can't control them properly.

Coilovers can get away with higher spring rates because they also include upgraded adjustable dampers that allow you to tune them to the spring rates depending on what kind of ride you want. Most will adjust for compression and rebound where a softer setting will be a bit easier on the street to a point and stiffer settings are more for smooth race tracks. Going too far in either direction of adjustment in relation to the spring rate will make the car ride as if it's out of balance. If the settings from front to rear are not tuned to each other properly you can also get that porpoise effect where the whole car oscilates out of balance front to rear.

A well setup coilover combo doesn't always have to be harsher on the street, but if the roads are really rough you would definitely feel the increased spring rates and firmer ride. Where Coilovers really shine is on a relatively smooth race track where weight transfer on a good setup is precise and predictable when compared to the OEM springs and shock combo that often lets the car roll too far for crisp handling.

I'm no suspension guru by any means and this is just what I've read over the years. Perhaps we can get someone with first hand knowledge to add to that as I didn't really find any good links that talk about the differences when I did a quick google search.