From the November 2017 issue
Scant bits of technology trickle down from racing to street cars anymore. Multimatic?s Dynamic Suspensions Spool Valve dampers are one of the few. The Canadian supplier?s dampers first appeared in the 2002 CART series, then migrated to Formula 1, and now populate about half the Le Mans starting grid. Aston Martin?s limited-edition One-77 was the first production car fitted with DSSV dampers and Chevrolet?s fifth-generation Camaro Z/28 followed in 2014. With their blend of street comfort and track-ready attitude, DSSV dampers are like shampoo and conditioner in one. Currently you can find them in the Ford GT, the Mercedes-AMG GT, and the Chevy Camaro ZL1 1LE and Colorado ZR2. Their simplicity is a thing of engineering beauty, so we uglied one up by cutting it in half with a band saw. Conventional dampers set compression and rebound forces by controlling the flow of fluid through orifices with stacks of flexible shims. Spool valves (001) dynamically vary damping force by controlling fluid flow through precisely shaped ports using a spring-loaded shuttle. Each DSSV damper contains two spool valves, one for compression and one for rebound.
Windows: There are six ports, or windows (002), on each street-car valve. Racing applications get fewer. The shape of the port helps define the damper?s baseline force-velocity curve?how much damping force is generated based on the vertical speed of wheel movements. The narrow end of each opening establishes the ...