Coilover kit to allow fine tuning of spring rate and ride height for competition vehicles. Requires simple modification of the factory upright. Contact us after ordering regarding proper spring rate selection. Use with Koni Yellow adjustable damper inserts. Available height adjustment exceeds stock fender clearance. For street use std Koni lowering springs should be used. Intended for competition vehicles due to the possibility for some extra noises and harder spring rates. Use with Koni sport-kit rear suspension. Currently for 9-3 99-02+03cv including Viggen. NG900 to come as needed.