Product Details

The Riaction GP1 Coilovers for the 2004-2013 Mazda Mazdaspeed 3 deliver a premium, adjustable suspension upgrade built for drivers who want more from their Mazdaspeed 3 than the factory setup can offer. These Mazda Mazdaspeed 3 coilovers are engineered to pair street comfort with canyon and track capability, giving you the stance, handling, and adjustability you've been chasing without compromising daily driveability.

GP1 Series Technology: The GP1 uses a digressive piston design that delivers firmer low-speed damping for flatter cornering and sharper response, while softening at higher shaft velocities to absorb bumps. If you want more control than a linear coilover without sacrificing ride quality, this is the set.

Every GP1 set features a monotube damper with 32 levels of damping adjustment, so you can tune ride quality to match the road, the weather, or your driving mood. Full-length ride-height adjustment separates preload from ride height — meaning you can drop the Mazdaspeed 3 to the height you want while preserving spring travel and shock stroke. Riaction coilovers for the 2004-2013 Mazda Mazdaspeed 3 are fully rebuildable and backed by a 2-year warranty, making the GP1 a long-term suspension investment rather than a disposable upgrade.

GP1 Series Technology

• Monotube linear damper with seamless 52mm electroplated carbon steel body
• 32-level damping adjustment (1-Way)
• 44mm CNC-machined 6061 aluminum high-flow piston
• 20mm piston rod for MacPherson applications / 14mm for non-MacPherson
• SAE9254 cold-wound linear main springs
• Multi-thickness valving shims for consistent damping
• Polyurethane oil seals and 7.5W suspension fluid
• Low-gas-pressure design for improved compliance
• Fully rebuildable — built to be serviced, not replaced

Features

• Full-length ride-height adjustment (preload-independent)
• 32 levels of damping adjustment
• Front camber adjustment via pillowball top mounts
• Optional Swift Springs upgrade (sold separately)
• 2-year limited warranty

The GT1 uses a linear piston — good low-speed control for body roll, turn-in, and weight transfer, with damping that follows a predictable curve through bumps. That balance makes it the right call for street, canyon, and occasional track days. The GP1 runs a digressive piston that sharpens low-speed response with higher initial resistance for flatter cornering, then softens at higher shaft velocities — a blow-off behavior that relieves harshness over potholes, curbs, and expansion joints. The GP1 is built for track-focused driving, autocross, and aggressive street use where you want the extra bite under load.

Short version: choose GT1 if you want the best daily-street-track balance — typically in stock and ship-ready. Choose GP1 if you want tighter response under load and don't mind the lead time on a built-to-order digressive tune.

Specifications

Vehicle Fitment

• 2004 Mazda Mazdaspeed 3
• 2005 Mazda Mazdaspeed 3
• 2006 Mazda Mazdaspeed 3
• 2007 Mazda Mazdaspeed 3
• 2008 Mazda Mazdaspeed 3
• 2009 Mazda Mazdaspeed 3
• 2010 Mazda Mazdaspeed 3
• 2011 Mazda Mazdaspeed 3
• 2012 Mazda Mazdaspeed 3
• 2013 Mazda Mazdaspeed 3