E46 M3 BC RACING ZR Coilovers

Description
BC Racing ZR Series coilovers are a 3-way adjustable, track-focused suspension system offering independent rebound, low-speed compression and high-speed compression adjustment. With 30 clicks of rebound, 15 clicks of low-speed compression and 12 clicks of high-speed compression adjustment, the ZR provides a substantial range of tuning. External reservoirs are used throughout, while McPherson strut applications also feature an inverted monotube damper design.

What it’s good for
Ideal for serious track cars, time attack, racing and high-level clubsport builds where suspension setup is a key part of extracting performance. The separate high and low-speed compression circuits allow the damper to be tuned for body control and driver inputs while retaining compliance over kerbs, bumps and surface changes.

What we like about it
The ability to separate low and high-speed compression is what makes the ZR particularly interesting. Low-speed compression can be used to influence how the car behaves through braking, turn-in and weight transfer, while high-speed compression gives you separate control over how the suspension responds to sharper inputs such as bumps and kerbs. This gives far more scope to optimise the chassis without simply fitting increasingly stiff springs.

Worth knowing: The ZR Series offers a serious amount of adjustment, but that also makes setup more involved. Changes to rebound, low-speed compression and high-speed compression all interact with the spring, tyre and chassis, so these are best suited to drivers who are prepared to test and develop the setup rather than simply fitting them and leaving the adjusters alone.