Shocking Technology: Multimatic’s Trick DSSV Dampers Explained

Shock absorbers are cheap to build, can last tens of thousands of miles under your vehicle, and does a decent job of absorbing shocks. But they aren’t perfect. They wear out quickly, losing performance as they wear. They also aren’t the most tunable part of the suspension. It’s difficult to make one that can control stiff springs while offering a smooth ride, for example, and tuning a shock can be as much art as it is science.

Lately, something new has emerged. A new type of damper that makes existing shock designs obsolete. And it’s for all types of performance cars. From the Aston Martin One-77  to the Ford GT to the Camaro Z/28. It even works on trucks, like the Chevrolet Colorado ZR2. It’s the Multimatic DSSV damper.

It stands for Dynamic Suspensions Spool Valve. Multimatic, the Canadian company that designed the dampers (and yes, that’s the same Multimatic that builds the Ford GT) explains it like this: “DSSV dampers regulate oil flow via precisely shaped ports. These ports, combined with the configuration of other elements within the valve, enable detailed shaping and optimization of the damper’s force-velocity curve.” Well, clear as mud then, right?

It gets better, “DSSV damping characteristics are mathematically predictable using Multimatic Specfinder software. Ideal damping characteristics can be accurately reproduced without extensive trial and error testing.”

Oh, ok then.

So how do these new magic dampers work, and why do you want them on your car? Let’s take a look.

The DSSV damper was first entered in the Champ Car World Series in 2002. On the Newman-Haas Racing cars, the dampers won seven races and the series championship. They then won five championships in a row. The dampers are on Formula 1 cars, including Red Bull Racing’s four consecutive championship runs.

Regular shocks use thin discs that move up and down with the shock piston. They move up and down inside a tube of oil and the flow of the oil through the holes in them controls the damping. Over time, the steel discs fatigue, which changes the stiffness of the shock. Debris becomes trapped in the layers, which degrades damping even more. They can only be tuned for a compromise of circumstances. Some are adjustable, but basically, you get one shot at setting the damping.

DSSV dampers still have a sealed tube full of oil, and a piston that moves with the suspension. But instead of thin discs, they have hollow sleeves with a spring inside. The sleeves have holes that are very precisely designed and machined. As the internal spring is compressed by the spool at the end of the piston, the holes in the sleeve are exposed, and the oil flows through them. This provides the damping force. Using a sleeve and spool valve is much more precise than using flexible metal shims. This allows more consistent damping, a longer life, and more predictable computer modelling that allows for more precise damping characteristics.

The DSSV dampers use one spool valve to control compression and one to control rebound. Compression damping controls the motion as the suspension hits a bump, and rebound controls the suspension as it recovers from the bump. This lets the automaker tune the two independently. And by changing the shapes of the openings, you can tune the damper to absorb small bumps with the cushion of a 1970s Cadillac while stiffening up to handle big bumps like a Ford Raptor. Or vise-versa if for some reason that’s what you wanted.

That shaping of the valve openings, and the ability to easily change the characteristics in mid-stroke, is what lets the dampers keep a massive sticky tire planted on a road course while soaking up curbing and rumble strip impacts.

On the off-road ready Chevrolet Colorado ZR2, there is an extra spool valve. This one is built into the damper’s main piston and is position sensitive. If the damper compresses to the extreme end of its travel – like if you send it off of a sweet jump, for example – the piston passes holes in the outer sleeve. Those holes are how the shock oil gets to the normal spool valves. So once the shock passes them, it is trapped in the main damper chamber. That activates the third spool valve. It’s much stiffer than the normal compression valve and stops the damper from bottoming out violently. It makes the ride comfy when you crash down off of a rock or land off of that sweet jump. The ZR2’s damper also moves the two main valves into another chamber beside the main body. That allows for more suspension travel in a shorter package.

Unlike magnetic shocks, where the fluid is changed electrically to suit various types of bumps and conditions, the DSSV damper is not adjustable. But the technology inside it lets suspension engineers decide exactly how the car should behave on different types of bumps before it ever hits the pavement.

So why aren’t they on more cars? Well, the dampers are still expensive. Chevrolet Performance offers a kit to upgrade your Camaro to DSSV dampers for $4,042. Compare that with the 1LE upgrade kit with traditional dampers that retails for $1,500. It’s tough to justify putting $4,000 worth of shocks on a midsize sedan. Even if it would make it ride well.

This is part of a series of in-depth features on in, under, or around-car tech. If there is something you’d like to learn more about, let us know in the comments below.

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