BC Racing ER Series - BMW 3 Series E92 M3 (2006-2013) (Sedan / Coupe RWD) (True Rear Coilover)

PLEASE NOTE THE IMAGE IS FOR ILLUSTRATION PURPOSES ONLY IF YOU REQUIRE SPECIFIC NEEDS SUCH AS TOP MOUNTS THEN PLEASE CONTACT US TO CONFIRM BEFORE ORDERING

BC Racing ER Series True Rear Coilovers – BMW E9X M3 Sedan / Coupe (2006–2013)

The BC Racing ER Series True Rear Coilovers for the BMW E9X M3 Sedan / Coupe (2006–2013) are an advanced, track-focused suspension upgrade designed for drivers looking for independent damping control, external reservoirs and a true rear coilover conversion.

The ER Series features 2-way adjustable damping, allowing compression and rebound to be tuned independently. Combined with external reservoirs and the True Rear layout, it provides a highly adjustable suspension platform for serious fast-road, track and competition-focused E9X M3 builds.

Why choose BC Racing ER Series True Rear for your E9X M3?

The BMW E9X M3 is a highly capable performance platform, and the ER Series is aimed at owners who want more detailed suspension control than a conventional single-adjustable coilover can provide.

Independent compression and rebound adjustment allows the suspension to be developed around tyre choice, spring rates, alignment, vehicle weight and circuit conditions.

The True Rear configuration replaces the factory-style divorced rear spring and damper arrangement with a complete rear coilover assembly, while the external reservoirs provide additional oil capacity for demanding use.

Key Features

• BC Racing ER Series True Rear coilovers
• BMW E9X M3 Sedan / Coupe application
• 2006–2013 fitment
• True rear coilover conversion
• Rear spring mounted around the damper
• 2-way adjustable damping
• Independent compression adjustment
• Independent rebound adjustment
• External remote reservoirs
• Increased damper oil capacity
• Improved heat management during sustained use
• Monotube damper design
• Adjustable ride height
• Rebuildable damper design
• Application-specific spring rates
• Custom spring-rate options available
• Adjustable top mounts where applicable
• Designed for serious fast-road and track use

True Rear Coilover Conversion

The main difference between this kit and a conventional E9X M3 ER Series setup is the rear suspension configuration.

The factory rear suspension uses a divorced layout, with the spring mounted separately from the damper.

With the True Rear configuration, the rear spring is mounted concentrically around the damper to create a complete rear coilover assembly.

This provides a more conventional motorsport-style suspension layout and can make spring changes and setup development more straightforward on dedicated track cars.

Independent Compression & Rebound Adjustment

The defining feature of the ER Series is its independent 2-way damping adjustment.

Compression adjustment controls how the damper responds as the suspension compresses, while rebound controls how the suspension extends again afterwards.

Being able to adjust these separately gives experienced drivers and suspension specialists greater control over how the E9X M3 behaves under braking, acceleration, cornering and changing track conditions.

This allows the suspension to be tuned more precisely around spring rates, tyres and geometry.

External Reservoirs

The ER Series uses external reservoirs as part of its advanced damper design.

The additional oil capacity helps manage temperatures generated during repeated damper movement and sustained hard driving.

For E9X M3s that regularly see longer track sessions, this can help maintain more consistent damping behaviour as temperatures rise.

BMW E9X M3 Track Suspension

The ER Series True Rear provides a highly adjustable platform for developing the E9X M3 chassis.

Independent compression and rebound control can be configured around other chassis upgrades such as:

• Performance tyres
• Adjustable suspension arms
• Uprated anti-roll bars
• Polyurethane or solid bushes
• Chassis reinforcement
• More aggressive alignment settings

For dedicated track builds, professional alignment and corner weighting can help make full use of the available adjustment.

Adjustable Ride Height

The BC Racing ER Series True Rear allows the ride height of your E9X M3 to be tailored around both appearance and performance requirements.

For fast-road cars, this allows the vehicle to sit lower with a more purposeful stance.

For track-focused setups, ride height should be considered alongside suspension geometry, available damper travel, alignment and corner weighting rather than simply lowering the vehicle as far as possible.

Choosing Your Spring Rate

Spring-rate selection is particularly important with a True Rear E9X M3 setup.

Because the rear spring acts at a different point in the suspension compared with the factory divorced arrangement, spring rates used with a conventional rear setup should not be directly transferred to a True Rear configuration.

The correct spring rate should instead be selected specifically for the True Rear layout.

Factors to consider include:

• Vehicle weight
• Tyre compound and width
• Road or track use
• Alignment
• Anti-roll bars
• Chassis modifications
• Circuit characteristics
• Driver preference

If you’re unsure which spring-rate configuration is appropriate for your E9X M3, contact us before ordering and we can help you choose a suitable setup.

Important True Rear Considerations

A True Rear coilover places the rear spring load through the damper mounting location rather than the original factory spring location.

Because this changes how suspension loads are transferred into the chassis, the condition and suitability of the relevant mounting points should be considered before installation.

This is particularly important on track and competition-focused E9X M3s where suspension loads can be considerably higher than during normal road use.

Professional installation and regular inspection of the rear damper mounting points and surrounding chassis are recommended.

ER Series Maintenance & Servicing

The ER Series is a rebuildable high-performance suspension system and should be maintained accordingly.

The dampers, external reservoirs, hoses, adjusters and mounting hardware should be kept clean and inspected regularly, particularly on cars seeing frequent track use.

Following BC Racing’s recommended servicing procedures will help maintain consistent damping performance and maximise the service life of the suspension.

E9X M3 Compatibility

This BC Racing ER Series True Rear kit is intended for BMW E9X M3 Sedan / Coupe applications produced between 2006 and 2013.

Please confirm the exact body style, vehicle specification and suspension configuration before ordering.

If you’re unsure whether this is the correct True Rear application for your M3, contact us and we’ll help you identify the appropriate setup.

What’s Included?

The BC Racing ER Series True Rear kit is supplied as a complete coilover suspension package for the applicable BMW E9X M3, including the front coilovers, True Rear rear coilover assemblies, springs, external reservoirs and relevant adjustable components.

Exact top-mount, spring-rate and reservoir specifications can vary depending on the selected configuration.

Explore More BMW E9X M3 Parts

Looking to improve your E9X M3 further? Explore our range of BMW E9X M3 parts and upgrades, including suspension, handling, performance and styling products.

BMW E9X M3 Parts – Shop parts and upgrades for BMW E9X M3 models.

BC Racing Coilovers – Explore the full range of BC Racing coilover suspension kits.

BC Racing ER Series – Browse ER Series applications across the BC Racing range.

Coilovers – Shop coilover suspension from BC Racing and other leading suspension manufacturers.