Bilstein Coilovers

Bilstein uses the same monotube gas-pressure shock technology across six main suspension kits, but only some of them are true coilovers in the strict sense (spring wrapped around a threaded shock body). The 5100 is a shock with an external adjustable spring perch that reuses your factory coil spring, not a coilover, even though owners commonly search for it as one.

If you're lowering a daily-driven car and want a bolt-in kit without touching a wrench after install, the B12 or B14 covers it - B12 keeps the factory-feel damping with Eibach springs, while B14 trades that for a height-adjustable coilover body. See coilovers by car to check what's listed for your specific chassis, including popular platforms like the VW Golf/GTI and BMW E9x 3 Series.

Drivers who split time between street and track usually move up to the B16, since the damping dial lets you soften the ride for a commute and firm it up before a track day without pulling the coilover apart. Truck and SUV owners leveling a factory stance for larger tires start with the 5100 because it reuses the stock coil spring and keeps cost down; the 6112 adds a coilover front strut when you need more front lift than the 5100's perch range allows. The 9100 is a different category entirely - it's sold as a bare coilover shock for fabricators building a long-travel off-road suspension, not a bolt-in kit.

Against KW, Bilstein's street kits (B14/B16) prioritize a more compliant, OE-like ride and wide dealer/retailer availability for parts and service, while KW's V-series and Clubsport lines generally offer a firmer baseline and more aggressive damping range for drivers who autocross or track regularly.

Ohlins leans further toward motorsport, with velocity-sensitive valving (DFV) aimed at drivers who want track-car behavior on the road; it typically costs more than a comparable Bilstein B16 setup.

On the budget end, BC Racing undercuts Bilstein on price and often includes camber plates or stiffer spring rate choices out of the box, at the cost of the long production history and OE-grade build Bilstein has from decades supplying automakers.

On B14, B16, and 6112, ride height is set by turning the lower spring perch up or down the threaded shock body and locking it with a collar - most installers use a coilover spanner wrench to turn the perch without marring the lock ring. B16 damping is adjusted with a dial at the top of the strut (or in-cabin on DampTronic/RideControl-equipped factory applications), independent of the ride-height adjustment, so you can firm up damping without changing the drop.

5100 lift height is set differently: it's changed by moving a snap ring to a different groove inside the shock body, which on most applications means partially disassembling the shock rather than turning an external collar. For torque specs, alignment needs, and a cost breakdown of either job, see how to adjust coilovers and coilover installation and cost.