Your search for "coilovers" revealed the following:
Eibach Springs, 2.25 Helper Spring
$54.00
Eibach HELPER spring. Essentially a zero rate spring to take up slack. A tender spring is often confused with a Helper springs. The Tender spring has a specific rate and length for tuning, the Helper spring is universal. Helper or Tender springs must be used with a spacer. Click here...
BMW E36/E46 Rear Control Arms with Sealed Bearing
$479.00
Tired of disconnecting the muffler just to align your car? Did you pay extra labor because your current control arms are difficult to adjust? The GC control arms can be adjusted without moving, removing, or bending anything. Chrome moly racing rear control arm manufactured in Germany. Sold in pairs.
BMW Rear Sway Bar End Link, Adjustable (Pair)
$169.00
Adjustable end link for many BMW rear sway bars.Ground Control exclusive machined billet stainless steel tapered adapters press into stock holes for a precise fit.Please do not compare to other kits that ask you to use a 3/8 rod-end into the BMW 10mm hole, it just doesn't work. That is...
BMW E36 Camber Plate-Sport (92-99 3 Series) and Z3 (Pair)
$499.00
The Ground Control SPORT plate, a special version of our camber/caster plates, toned down for dual-purpose cars. Uses a proprietary upper perch which can reuse the stock spring insulator. A work of art, carved from a single piece of billet aluminum. That is the only way to describe this new...
ERS coupler, 2.50 springs (Each)
$28.00
Eibach Spring coupler.  Used for joining 2 Eibach 2 1/2 inch I.D. springs together. Primarily used with tender springs (see catalog) and helper springs.  The formulas for calculating coupled spring rates can be found at http://www.eibach.com SOLD INDIVIDUALLY
$165.00
THIS IS AN ADDON FOR ANOTHER PRODUCT ON OUR STORE. DO NOT PURCHASE.
COMPLETE HELPER SPRING UPGRADE
$330.00
THIS IS AN ADDON FOR ANOTHER PRODUCT ON OUR STORE. DO NOT PURCHASE.
F8X Adjustable Rear Control Arms M2/M3/M4/GTS
$714.00
Our adjustable rear control arm kit for your F8x series BMW allows you to have all of the control over your rear wheel alignment. The kit includes 8 arms total, 4 per side. All arms use heim joints and misalignment spacers made to fit precisely in your F8x rear chassis.