Zeal Function-X Coilovers Honda Civic Si 03-05

For the next generation hard user, we’ve developed the Function-X Series. The Function-X is now born and is currently the most popular race application amongst the ZEAL line-up. With advanced damping capabilities in effect, our efforts have recently focused towards our new “X-Coil Hyper Spring”. Through consistent and progressive research and experience, we’ve improved spring quality to achieve an even smoother and more responsive feel and ride. The ability to grasp precise road data has improved. The X-Coil spring achieves exactly this. Our Dynamometer Data proves this with stable rebound and compression levels (within a 0.1 Meter Per Second range) for level travel at very low speeds, very high speeds, and everything in between. By keeping very detailed, precision spring motion in mind, we are able to set the shock’s piston valving to superior levels. The combination of the shock and spring is superior. Our Linear Spring Motion with no Friction Loss is superior and the shock can be adjusted very precisely (Function-X includes 30-Way Damping Adjustability), thus the setting levels have broadened and can be fine-tuned with advanced precision and feel. Lightweight aluminum upper mounts, spring seat preload and spring seat locks, height-adjustable lower brackets and lock seats (for non-strut type applications) include a durable, Alumite finish for rust proof characteristics. Steel shell casing includes a special chromate plating for rust proof characteristics also. Adjustable brackets are newly designed and slender. Driving feel is amazing for the hard-user. MacPherson Strut-Type systems are specifically produced as an inverted-monotube type.

Spring Rate:
Front: 12 kg/mm
Rear: 10 kg/mm

Spring Length: 178mm

Note: Rear is ID65