COMPETITION coilover key features: Aggressively tuned for drifting at low ride height. Our classic Competition coilovers for S13 are specially designed to be shorter to allow low ride height without having to place a custom order. Spring rates are 10kg/mm in the front, 8kg/mm in the rear standard. Dampers are tuned aggressively to work well even at low ride heights. Firm ride, but not overly stiff. Perfect for those that seek a low/stylish car that still performs at the track! 1) Low ride height ability 2) Fully threaded damper & lower mount allows vehicle height to be adjusted independent of the spring preload and without using a helper spring. We always suggest zero spring preload. 3) Large range of rebound adjustment is available at the turn of a knob on the top of each damper 4) Allows full soft to full hard damping change in just 12 clicks with a simple 3mm allen. 5) Replaceable & Custom Tunable Damper. Easily replace damaged parts at a fair price. 6) Custom spring rates are available to special order with a proper damper tune (4-32kg) Contact us for inquiries regarding custom spring rates, damper tuning, adding features such as helper springs, air bags, etc. 7) Pillow ball upper mount on front and rear allow coilovers to freely pivot with track width adjustment. Never have to worry about wearing out rubber top bushings. 8) Spring upper perch provides independence between the spring and the pillow-ball 9) Billet T6061 lightweight aluminum Lower mounts with rear lower urethane bushing 10) All aluminum components are hard anodized. Lightweight aluminum construction reduces unsprung weight. 11) 2 collar wrenches are included 12) Lifetime manufacturer defect warranty. Individual parts available for purchase to repair crash damage.