coming from F1 to Baja: Multimatic’s Clever Spool-Valve Dampers Explained
Car-development engineers are invariably discontented with the status quo. in which’s especially true in ride-along with-handling development, where twin-tube shock absorbers—more accurately called suspension dampers—are right now under scrutiny. These 100-plus-year-old devices are finally prime candidates for replacement by more sophisticated hardware.
Twin-tube dampers are inexpensive to manufacture, serviceable for tens of thousands of miles, along with entirely suitable for mainstream use. in which said, they’re susceptible to wear, which deteriorates their performance over time, along with they lack the tuning flexibility offered by newer damper designs.
Enter Multimatic, a Canadian enterprise in which strives to be every car company’s problem solver. This kind of suspension-systems along with composite-Centeng specialist is actually currently Ford’s ally for constructing its GT supercar. In addition, Multimatic’s Motorsports division incorporates a lengthy history of designing, engineering, constructing, along with campaigning race cars for top-series competition around the globe.
In 2010, Multimatic applied for a patent on an innovative suspension damper. Code named DSSV, for Dynamic Suspensions Spool Valve, This kind of design initially proved its merit by helping Newman-Haas Racing win seven of the 19 races along with the driver’s championship inside the 2002 CART series. DSSV hardware became mandatory equipment in a few some other major racing series between 2006 along with 2015. Red Bull Racing used them to win four consecutive Formula 1 titles (2010–2013) along with nearly half of This kind of year’s Le Mans 24 Hours competitors swear by DSSV dampers.
Conventional dampers use multiple thin discs covering ports inside the piston moving up along with down within a tube containing hydraulic oil to generate the forces in which control Centeng along with wheel motion. The flexibility tuned into these discs—along with the size along with shape of the ports they cover—determines how fluid flows between the chambers above along with below the piston. The greater the flow restriction, the higher the damping force.
While in which principle is actually sound, problems arise with mileage. The steel disc material is actually subject to fatigue, which diminishes its strength along with stiffness. Bits of debris coming from the damper seals, piston, along with shaft become trapped between the disc layers, altering their damping qualities. Anyone who has owned a high-mileage car with clapped-out shocks knows in which the term “handling” no longer describes its dynamic behavior.
The some other shortcoming with conventional dampers is actually in which they can’t be tuned to cover the full scope of road driving, track lapping, along with off-pavement excursions in which ambitious manufacturers are striving to cover.
Multimatic’s DSSV dampers retain basic components such as a sealed tube filled with hydraulic oil along which has a piston in which moves within in which tube in sync with suspension motion. The difference is actually in which the thin discs are replaced which has a pair of hollow cylindrical sleeves nested concentrically within each some other along with held apart by a coil spring. Suspension motion forces damper oil inside the sleeve cavity. When in which internal pressure is actually sufficient to overcome the spring force, one sleeve moves slightly with respect to the some other, uncovering apertures, which allow oil to move to the opposite side of the piston. One sleeve valve regulates compression damping; another controls rebound damping.
The beauty of This kind of arrangement is actually in which the sleeve valve components are not susceptible to wear or fatigue. The stiffness of the coil spring along with its preload along with the shape of the apertures facilitate three distinct damping curves. A linear “curve” provides damping forces directly proportional to the velocity of the suspension movement. Progressive damping characteristics mean in which the force rises gradually with suspension velocity. Digressive damping is actually a steep initial rise in damping followed by the force curve leveling off at some specific suspension-travel velocity. Multimatic has software called SpecFinder in which allows ride-along with-handling engineers to quickly along with easily pick spool valves in which deliver the damping curves they desire.
What proof do we have in which DSSV works as touted? At Car along with Driver’s 2014 Virginia International Raceway Lightning Lap event, the Chevrolet Camaro Z/28 along with its standard Multimatic DSSV dampers bested a Porsche Cayman S, a Jaguar F-type R coupe, along which has a BMW M4 in its class. In Turn 1, the item cornered at 1.16 g, matching a Porsche 918 spyder as the grippiest car we’ve experienced in in which bend to date. We went on to extol: “Holding the fear pedal to the floor is actually necessary to discover the genius of the Z/28, which is actually in which nothing scary happens. The curbing, the bumps, the speed, along with the violent transitions don’t affect the Camaro’s trajectory one micrometer.” We also crested the hill at the top of the climbing esses at 118.5 mph, an all-time Lightning Lap record at in which time. As compression began going into the following left-hander, the Z/28’s suspension was so capable in which the challenge was resisting excessive use of the brakes. While the astute damping characteristics were at the heart of This kind of Chevy’s track prowess, credit must be shared with the overall suspension tuning along with the Z/28’s humongous Pirelli P Zero Trofeo R tires.
Camaro lessons learned, Chevrolet partnered with Multimatic a second time for the 2017 off-road-rated Colorado ZR2 mid-size pickup. Here, DSSV technology has moved forward another step with what Multimatic calls Position Sensitive Damping (PSD) to provide specific damping characteristics in different areas of the suspension’s travel. Combining three spool valves which has a remote nitrogen-charged fluid reservoir [see top animation] allowed engineers to tune the ZR2’s dampers for optimum performance both on-road along with in severe off-road use. The added reservoir supports longer wheel travel along with increases the amount of working fluid to resist overheating. The extra spool valve provides the damping needed to control extremes of wheel movement during high-impact compression cycles.
Chevrolet along with Multimatic used two approaches to meet their performance targets. First, a computer-aided-engineering design of the DSSV damper was created using ADAMS (Automated Dynamic Analysis of Mechanical Systems) software. This kind of step occurred well before the first running Colorado ZR2 was constructed. After the dampers along with the entire vehicle were validated in virtual form, on- along with off-road test driving of prototypes began. This kind of included desert runs, rock crawling, high-speed trail drives, paved-road evaluations, along with stints on Multimatic’s four-post shaker rig.
This kind of analysis helped reach ambitious goals. One was minimizing the ZR2’s frame weight while keeping peak loads below the acceptable limit by tuning the dampers to absorb more impact energy. some other aims were to reduce the peak vertical movement of the ZR2’s center of gravity by 40 percent along with the driver’s hip upward displacement by 50 percent with damper tuning. Combining DSSV with PSD lowered the peak vertical force at the front tires by an impressive 35 percent while traversing a challenging “whoops” road profile at General Motors’ Milford Proving Ground.
- 2017 Chevrolet Colorado ZR2: A Highly Capable Off-Roader with an Available Diesel
- This kind of 1938 Film Explains (Simply) How Car Suspensions Work
- Diff Definitions: Each Type of Automotive Differential Explained
We’re looking forward to sampling the Colorado ZR2 alongside Ford’s larger F-150 Raptor at an appropriately difficult off-road venue, such as Mexico’s Baja 1000 course. Unfortunately, Multimatic has no plans to sell DSSV dampers inside the aftermarket except for replacement parts engineered for the Camaro Z/28. They’ll work on any sixth-generation Camaro, so anyone owning a 2016 or newer Chevrolet pony car can upgrade to at least partial Z/28 specs through GM’s service parts organization.