BC Racing ER coilover suspension for Mazda MX-5 / Miata NA/NB (1989–2005)

BC Racing ER Coilover Suspension Mazda MX-5 / Miata NA/NB/NBFL (1989–2005)

Premium coilovers with external reservoirs and independent adjustment – maximum control for street and track.
The BC Racing ER Series is the top-tier suspension option for MX-5 drivers who demand the highest level of tuning precision. With external reservoirs and separate compression and rebound adjustment, the ER Series lets you fine-tune balance, grip, and response for your exact setup.

Technology & Construction

• Digressive piston & damping curve – higher low-speed damping for body control, reduced high-speed damping for kerb/bump absorption
• External reservoirs – increased tuning range and stable performance under sustained load
• Monotube damper design for consistent performance
• Dust boots to protect damper seals
• Bearing-mounted upper spring platform for smooth operation
• Tapered bottom mount locking collar to prevent loosening under load

Adjustability

• 30 clicks compression adjustment via the external reservoirs
• 30 clicks rebound adjustment from the top of the damper
• Ride height adjustment independent of spring preload – full damper travel retained
• Camber-adjustable top mounts (depending on model)
• Pillowball top mounts for precise steering feedback

Spring Rates

• 8 kg/mm (front) & 6 kg/mm (rear) – ideal for street and track
• Custom spring rates available upon request

Performance Advantages

Separating compression and rebound adjustment allows you to tune vehicle dynamics with precision:

• Braking: compression helps manage weight transfer to the front tyres for grip and trail-braking stability
• Corner entry: rebound prevents the suspension from extending too quickly, keeping the front loaded and reducing understeer
• Corner exit: balanced damping lets you get back on throttle sooner, improving traction and exit speed

Compatibility

• Mazda MX-5 NA (1989–1997)
• Mazda MX-5 NB / NBFL (1998–2005)

BC Racing ER is the ultimate choice for MX-5 owners who want true suspension tuning capability: premium hardware, independent adjustability, and professional-level control for both road and track driving.

In 90% of cases our products are in stock; however, depending on availability, shipping may take up to 4 weeks.