How the DSSV shocks work on the new Chevy Colorado ZR2

Originally the dynamic suspension for the brand is best known in racing circles, circuit racing and some

broad rally cast up as well. For the small valve technology we transferred over from the machine valve dampers about

probably 10 years ago maybe a bit longer than that. in the racing world and our first actual road application of the small valve technology was the C28 Camero

last generation C20A Camero and then GM approached us about the truck application so we put it together with GM and decided on the best art

architecture for the Dancault. And the actual valve inside it is what the difference between the typical shim valve and these is it's a hydraulic

ball valve. So we have a coil spring inside this tube and shaped windows on the side and

we call it the shuttle inside and move and expose the window to allow oil to flow from the inside

through the window and escape. And by shaping the window and changing some various other components, the spring rail and things

we have very, very precise control over the shape of the force velocity curve

and being able to do different things with the force velocity curve than what you can do with a shin valve

really allows you to tune the performance of the vehicle very very precisely

So these two valves, we can show you, we have, there's actually three in total in the damper

We have a cutaway, or a plastic transparent damper here, so that's just a plastic version of that guy

And the two main small valves, one for rebound and one for compression six

in the central chamber The outer chamber is just a gas reservoir It happens to be an incorporated all in one piece but that could be a remote reservoir but it all attached in this one So we got the two in the valve body

And when the piston is in the normal range, you see these holes in the inner tube

when the piston is between the cover and the holes in the inner tube

the oil, all the oil is pumped through the main valves. So in compression, the oil below the piston is pumped down the tube

down the tube, comes out through these holes in the inner tube, and then makes it way between

the two tubes, then out into the compression valve, up through the compression valve, and

then recirculates in through the top of the damper. You see the forts up here. In Rebound

it does the opposite. The oil is pulled, by the piston, pulls it out the top, goes down

the outside of the damper, in through the rebound valve, then recirculates into the bottom

to recoup underneath the piston. Once the piston passes these holes, so you can actually

see this at some point, see the piston goes past those holes, I can see that, but the piston's

passing it. And once the piston passes those holes, the oil is trapped between the piston

and the bottom of the tube. And the only way place for it to go is back through the piston

So there's a third independent small valve inside the piston itself that controls the compression

forces towards the end of stroke. So that valve is a lot stiffer than the main valve

So as you approach end of stroke in a big off-road event, it absorbs a lot of energy in

the last third of the stroke of the damper. So that's the position sensitive bit, the PSD as it's been, as we call it

So this technology basically is a readover from circuit racing ultimately, but the first

The flexibility of the tuning really allows you to apply it to any vehicle you want and get a really good result

So this is a, there would be a Formula One version of the same thing

So it actually a very similar architecture hydraulically but obviously on a vastly different scale and at a vastly different cost But it the same exactly the same concept

The valves with the shaped windows and the coil spring is in the race dampers, as is in these and the Z28

But this is the only one that has the position sensitive portion of the architecture

The second benefit of it basically pumping the oil around the damper

around the outside of the damper between the two tubes, is the working fluid is always being moved past the outer surface of the damper

which is aluminum. So it's really good for heat transfer and really good for keeping the dampen here

It starts here that's saying we're adapting the school valve technology that was successful in other road cars, including the Camaro Z-28

We have unique school valves for compression and rebound. We're taking those valves, the exact same valves, and we're applying them to an application for off-road

That gave us, moving them off the piston gave us more travel for the available space

Also allowed us a chance to add a third valve, a third school valve, on the piston. Good

So the damper could help the vehicle respond to what it would experience off-road

So that could be tuned just to handle those loads separately from the on-road driving range drives

That way the damping is unique in the different ranges of position, travel, the damper

So taking the spool technology from the Camero and applying it to the gear

and how it works is when you driving on the road the piston is moving up and down in the middle of the damper So it doesn get to the extremes When you can press the damper over bumps the piston gets pushed all the way to the bottom of the damper

Our architecture allows the damping characteristic where the piston is down here to be different

tuned, and optimized just for that region, separately from driving on the road

So the oil flows inside this range, out these transfer ports, through the angular space across the bridge and through the valves

And then in a rebound, it's going the opposite direction. It's coming up the inside tube and out between the two tubes and back through the valves

the rebound valve. But when you end up bump, the piston goes past those transfer ports

There's nowhere for the oil to go. So it would be hydroly for lock except that we added that third spool valve on the piston

which becomes active under the forces past the port transfer ports. and then it's tuned optimized just to manage the loads of the huge challenge

In fact, you get from a landing or hitting a large bump. So the school valve inside here is tuned just for that differently from the road school valves

And the road school valves are tuned optimized just for road driving

and there's no compromise in them when you drive on the road for the vehicle to be able to do the off-road events

Also, when it's fully extended, when you're going to be able to do the off-road events. route

When you do it gets close to being airborne, it becomes airborne, you don't want your wheel to go slamming down in the full extension

So there's this, another little piston that goes in a hydraulic cup, which creates rebound

damping force. It allows it to manage the energy, so the wheel is it smacked against the end of the travel

It's a soft transition to the end of travel. So each operating range, road driving range, compression range, rebound range are optimized

with the course of loss of characteristics uniquely for that region without compromised to be able to

be able to start