BC Racing BR Series Coilovers – Type RN Lotus Elise Series 2
The BR series coilovers use a large 46mm diameter piston in a 53mm diameter damper body to maximise oil capacity. As the damper unit opearates the oil contained within heats up. The viscosity of oil changes as its temperature varies which can lead to changes in the damping characteristics of the unit.
BC Racing only use a very high quality oil with their coilovers but go that extra mile to maximise performance and build their BR range with a large 53mm diameter damper body. 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.
External reservoir ER Series
BC Racings premium flagship coilovers are the external reservoir ER Series with separate compression and rebound damping adjustment. The ER Series coilovers bring with them the high quality and unique features seen on the BR and RM type but have the additional benefit of external reservoirs and the ability to allow the end user to individually adjust and set compression and rebound damping rates.
The external reservoir ER Series coilovers allow BC Racing to increase the oil capacity of the damper unit. The additional oil capacity reduces peak oil temperatures which decreases variations in damping rates due to oil viscosity changes. The reduction in damping rate variations improves handling and ultimate on road and track performance.
Separate compression and rebound damping adjustment
By separating the adjustment for damping compression and rebound the ER Series allows you to dial the vehicle in to your exact needs. When braking hard whilst approaching a corner you want the car to transfer weight to the front tyres to maximise grip for the braking effort and also to allow you to trail brake into the corner without the car understeering.
As you start to lift off the brakes on corner entry you don’t want the suspension to snap back up too quickly as this will remove the loading from the front tyres too quickly and lead to understeer. As soon as the car starts to understeer you need to wind off the steering lock to reduce the work effort applied to the tyres to allow them to regain traction. This slows the vehicles ultimate speed.
The compression damping adjustment allows you to fine tune the way the car rolls onto its front tyres during braking and the separate rebound adjustment allows you to fine tune the way the car responds as you come off the brakes to enter the corner proper and keep the front end hooked up. This allows you to get back on the power sooner and maximise corner exit speed. Corner exit speed is vital because this determines you maximum speed achieved down the next straight.