I'm considering getting coilovers but I never had much interest in them before so I really don't know that much about them. When I looked around at different types online a few things were unclear to me. First is the drastic price difference: I see some coilovers going for over $1000 and then others going for around $100 (even as low as $50 on ebay!), Obviously there are different types of coilovers if there are 2 completely different price ranges but what's the difference? Also I'm not clear on the stiffness. Does stiffness change as height is changed or is it constant? And does the stiffness change by manufacterer or are they all around the same? Last but not least, with coilovers do you still use your shocks? I read somewhere that coilovers function as springs and shocks so does this mean I'd have to remove my shocks?

Wow, lots of good questions. First off, the difference in price is because some you see (ones $350 and under) are just coilover sleeves that you slip over your existing shocks, or aftermarket ones if you change the stock ones out. Ride quality of them is negledgable, and you get what you pay for with them basically. They can rattle a lot if you get cheap or crappy ones. Ground Control and Skunk2 are the best ones by far, both retail for around $300. The ones you see for about $800 and up are TRUE or FULL coilovers. That means they are an adjustable coilover spring specially matched to a threaded shock. It's all one piece in terms that the springs come with the shocks, and both are precisely matched to eachother, so there's virtually no chance of blowing them out, or overworking them because the spring rates are more than the shock can handle which is the case of most coilover sleeves.

As for stiff ness, the more you compress a spring, the stiffer it's goung to react because now it has lest room to move around in for one, and it has more resistance working against it. Stiffness WILL change by manufacture because the thickness of the spring, or even that materials made to make it all affect how it's going to react when compressed. Dropzone and APC coils are gonna feel different from Skunk2's or Ground Controls. Even those 2 will differer in feel from eachother. Ground Control sleeves are good, because you can custom order specific spring rates with them, but if you go stiff than they are made, you almost can't get away with anyother shock besides Koni Yellows. Of course with full coilovers, almost any you get you can order custom spring rates with them, and the manufacture can specifiacally adjust the valving inside the shocks to handle the adjusted spring load.

Putting on coilover sleevs is like putting on normal non-adjustable lowering springs, you either keep your stock shocks if you decide to, or you can get aftermarket shocks for them. Eitherway, you HAVE to have shocks to go with them. If you get true coilovers like Teins for example (which is what I have on my Civic), you get rid of BOTh your stock shocks and springs, because the all-in-one units replace them.

If you have any other ?'s about this, feel free to ask away. :)