Progressive VS Linear Rate Springs, ed ju cate me.... Options

[Aaron Cox]

i have opinions of both.....

i run linear 140's..... a friend of mine has progressive 165's.

what are the pros and cons of each.

[lapuwali]

Pretty much, that's it. You can run a softer initial spring rate, but a compressed rate that's stiff enough to prevent bottoming. Note that linear rate springs don't always translate to a linear spring rate at the wheel. If the spring axis is tilted significantly wrt the plane of suspension movement, the rate will naturally change as the suspension compresses. On the 914, the axis of the spring is more or less in line with suspension movement, so the rate is reasonably linear (on the rear, of course).

Gas-charged dampers also often provide some springing action in compression, so the damper also has to be factored in when discussing wheel spring rate. This rate is always exponential. There have been "dampers" which had air or nitrogen cells in them that provided 100% of the springing. Rubber springs also provide a non-linear springing effect, and quite a few cars rely on compliant bumpstops when cornering to provide some springing.

It's not at all difficult to get used to spring rates that "change" mid-corner. As noted, the tires (which are also part of the spring system, and being pneumatic, are exponential springs) provide a significant spring effect.

In short, pure linear springs do not exist on real-world cars.