FPS is proud to present the first ZERO-SHOCK piston with 100% Made in Italy carbon fiber technopolymer body and full metal teeth.

This system patented by Fps allows to attenuate the stresses that the rack transmits to the piston body and it makes the assembly enormously more resistant and reliable than a normal piston.

For the material of the piston was chosen a carbon fiber reinforced technopolymer with added elastomer with high mechanical performances and a very low friction coefficient.
The rack has been manufactured using MIM (Metal Injection Molding) technology because this production process guarantees dimensional precision and strength equal to those of solid machining.
The rack is presented with the second missing tooth and with the third already lowered by 3 tenths of a millimeter because this configuration predisposes the piston itself for a correct angle of engagement (AOE) and makes it suitable for high speed.
The type of metal injected is SAE 4650 + HRC38-42 hardening treatment which is currently considered the best material on the market for this type of use.
The sliding guides are designed to minimize friction and retain the lubricant for a long period of time.
The rack seat is decentralized to favor the coupling between the piston teeth and those of the sector gear.
The longitudinal reinforcements at the sides of the teeth increase the robustness of the piston and avoid contact of the rack with the inner wall of the cylinder.
Special ribs decrease the contact surface between the spring and the internal part of the piston body and consequently also the friction between metal and technopolymer is decreased during contraction and elongation due to the firing cycle.