T4 Alu Progressive Shock System - Set (2) - PSS
Will fit to each kind of T4.
Dampers 308307-O are necessary.
No complete dampers, only optionals to upgrade your existing dampers!
Innovative progressive shock system for touring cars for improved traction and steering characteristics. Shock insert has 3 triangle cuts and is used with piston without holes. The hardness of the shock is influenced not by the holes in the piston but with the insert. The insert is mounted into the shock with wider surface on the bottom of the shock and narrower on the top.
When the piston is at the bottom of the shock, it moves softer and dampening becomes harder when the piston is going to the top. This means that the shock dampening is softer in the first part of movement and becomes harder when the car is moving more. The shock inserts must always be used with pistons without holes, must be used both front & rear, and only on asphalt. The same oil is used in these insert-equipped shocks as with standard shocks. The inserts are CNC-machined from premium Swiss 7075 T6 aluminum, and are black coated. The pistons are molded using special processes & composites to ensure roundness, while maintaining maximum stiffness and durability. The pistons are additionally precisely grinded.
There is a mistake in the manual of T4 2020. Also the correction of the PDF manual might be still complicated.
308029 = ULP = kit shocks 308308 - ULTRA low profile => SHORT
308039 = SLP = optional shocks 308307 - SUPER low profile => LONG