BC RACING SUSPENSION COILOVER KIT - SUBARU (IMPREZA WRX)
BR Series Street and Track Coilover
Pillow ball upper mountCamber adjustable top mountsAluminum top plates30 way adjustable dampingAdjustable spring platformHeight adjustment via bottom mount to retain full damper travelBearing mounted upper front spring platformDust boot to protect damper seals* some features are dependent on model
BR Series: Monotube Damper for street and track use
The BR series coilovers use a large 46mm diameter piston in a 53mm diameter damper body to maximize oil capacity. As the damper unit operates the oil contained within heats up. The viscosity of oil changes as its temperature varies which can lead to changes in the damping characteristic of the unit.
BC Racing only uses special designed high quality oil with their coilovers that go the extra mile to maximize performance. This increases the capacity of the unit which increases the volume of oil contained which in turn reduces the peak temperature and so significantly improves damper performance.
Damper testing and matching:
Damping adjustment allows you to fine tune your car to suit your needs and the cars intended use. Adjustment should always be made in axle pairs, so both fronts must be tuned the same and both rears must be tuned the same.
Decreasing front damping will speed up the weight transfer as you apply the cars brakes thus increasing front traction. You want some degree of weight transfer to occur to load up the front tires to maximize braking ability and to help the front end hook up for corner entry. The front loading helps prevent under steer.
Such subtle tweaking of the damping rates can make a big difference to the way the car handles. Coilover and after market damper manufacturers run quality control system that can lead to a large variation in damper to damper performance. This means that you can have different damping rates at each corner of your car even when the dampers are dialed in to the same setting via their adjuster. Because damping settings are so crucial to a vehicles handling, this can lead to a handling imbalance where the car will pull slightly under braking and its turn in and mid corner handling characteristics can differ from left to right hand corners.
It’s because the damping rates are so crucial that BC Racing checks each and every damper they produce on an in house damper dyno. The compression and rebound damping rates are recorded and the coilover kits are only put together using matched dampers. Through this in house individual checking BC Racing can be confident that the kits are produced with matching dampers. BC Racing run to a tolerance level 3 times more accurate than general original equipment manufacturers so the difference in damping rate between BC Racing units is a third of that aimed for by most original equipment manufacturers.
Straight replacement for original equipment:
The BC Racing coilovers are a direct replacement for the original equipment. Unlike other brands of coilovers, the BC Racing range do not require brackets fabricating, cable ties or jubilee clips to install. The bottom mounts come with all brackets to take the original ABS sensor leads, brake lines, anti roll bar drop links etc. BC Racing provides a straight forward and simple install, just take off your original equipment suspension and install the BC Racing Suspension.
Corner weight adjustment:
The lower spring platform of the BC Racing coilovers are adjustable. This allows the car to be set up for corner weighting to achieve perfect balance and ensure that maximum tire efficiency is achieved. The car needs to be placing equal weight on each tire on an axle so both front tires need to be taking equal loading as do both rears. This makes sure that both tires are doing their equal share of work when cornering which increases overall grip, maximizes corner speed and reduces lap times.
Ride height adjustment:
Ride height is determined by the position of the coilover bottom mount. The mount can be wound up and down the damper body to give a full range of height adjustment. Because ride height is determined by an adjustable bottom mount rather than spring platform you retain full damper travel regardless of the ride height run.
BR coilovers feature 30 way damping adjustment that combines both rebound and compression in one adjuster for simplicity and ease of use. This adjustable facility allows you to fine tune the vehicle to meet the required needs of each consumer.
Pillow ball upper mount:
Many of the BC Racing BR coilovers come with pillow ball upper mounts. The mount itself is made from aluminum alloy, anodized and then bead blasted to give a high quality, durable finish. The pillow balls themselves are of Japanese manufacture and their solid nature eliminates any flex or play associated with the standard rubber mounts so improving response and handling.
If it’s possible to include camber adjustment on your vehicle then the BC Racing coilovers automatically include camber adjustable aluminum pillow ball top mounts. These feature the same high quality Japanese manufactured pillow ball but give the added benefit of an adjustable top mount that allows camber to be set to suit your needs be it road, track or drift.
The damper units are black chromed steel to give superb durability. The aluminum components (top mounts, locking collars etc) are anodized and the steel lower mounts go through an electrophoretic deposition process followed by powder coating. A random selection of steel components (brackets, dampers, screws etc) are put through a salt spray test once a month to check the quality of the protective processes and that anti corrosive properties are kept at the highest possible standard. As with any metal exposed to the environment BC recommends the use of synthetic lube be applied to the exposed threaded portion at regular maintenance intervals.
High quality coil springs:
BC Racing coilovers only use the highest quality steel for their spring manufacturer. They are produced from SAE9254 high strength durable cold wound steel. The springs are compression tested through over 500,000 cycles with less that 5% deformation.
Patented concave lower locking collar:
Coilovers use a locking collar to prevent the bottom mount becoming loose. BC Racing utilizes an innovative and patented designed lower locking collar with a beveled edge that seats into a corresponding bevel in the coilover bottom mount. This vastly increases the surface area that the locking collar works on and so prevents the common and dangerous problem of the locking collars working loose.
High quality oil:
BC Racing dampers use a sophisticated shim stack design and high quality oil to consistently control the compression and rebound speed of the damper rod even under the most extreme conditions. As the vehicles travels over rough ground the compression and rebound motion of the damper rod heats the oil. Poor quality dampers use cheap oil whose characteristics alter with varying temperatures. It’s vital that high quality oil is used that can maintain consistent viscosity under a wide temperature operating range. Once the oil starts to degrade, its properties change leading to damping changes leading to changes in the vehicles handling characteristics.
BC Racing ensures that only high quality oil is used so that damping rates are maintained not only for the moment in hand but that long term longevity is maximized with oil that doesn’t degrade quickly over time thus extending the dampers operating life significantly.
Nitrogen pressurized dampers:
When you work a damper hard on track or on high speed bumpy roads you can cause the oil to aerate and cavitations can occur. This cause foaming which effectively reduces the oils viscosity and so reduces the units damping effect. High quality oil goes a long way to help reduce this problem but BC Racing go one step further and pressurizes the dampers with nitrogen. The nitrogen exerts a pressure on a floating piston which in turn exerts a permanent pressure on the oil dramatically reducing aeration and so improving the consistency and quality of the damping. The pressurized nitrogen also adds an additional element of effective spring rate to the damper unit.
Bearing mounted upper spring platform:
Because the spring twists as it compresses it is very important to minimize friction between the spring and its seats. If this tension is not relieved then spring binding can occur leading to the spring rate effectively altering slightly as the spring compresses and extends. The tension generated can lead to rapid deterioration of the spring perches and in extreme cases can cause the spring platform and locking collars to loosen. This can lead to the platform and locking collars ‘walking’ down the damper resulting in an uneven ride height and danger of the spring dislocating under full damper extension.The friction between spring and seats also has an effect on steering effort as the springs are physically turned with the wheels. This introduces additional unnecessary friction into the steering system which has a knock on detrimental effect on the vehicles handling characteristics.The bearing mounted upper spring platform is one of BC Racings innovative designs. By vastly reducing friction between the spring and its seats the BC Racing units avoid the above problems thus improving the efficiency of the steering system and allowing the spring and damper to work as designed.
Damper adjusting extenders – BC Racing coilovers we can offer pairs of adjuster extenders. These attach to the adjuster knob on the top of the coilover in seconds with a simple grub screw design.
Pillow ball top mount – Various applications come with the standard hardened rubber top mounts to ensure the highest quality ride. However, upgrading to pillow ball eliminates the flex inherent in even the hardened rubber mounts improving handling for those looking for the ultimate driving experience.Custom Spring Rates and Valving – BC Racing coilovers can be custom ordered with custom spring rates and custom valving at no additional fee. These are considered special order items and require a 10-15 day wait period.