http://www.dmshocks.com/

As some of you will know, the size of the piston in a shock is extremely important in maintaingng consistent shock damping etc.

THe moton from king i think has a 22mm id piston.

Check out these beasts!!! 50mm app for the s2000


Think I will have to call them

 

Actually, a huge piston is only needed in strut-type applications where the shock forms a structural member of the suspension and takes loads on it other than those compressing and extending the shock (ie sideloads).

In the S2000, because of the double wishbone design, the shock sees no loads other than those that force it to compress and extend. Therefore, a large piston shaft diameter is not necessary. Too large a shaft will compromise suspension reaction by adding unnecessary weight.

 

Umm yes and no.

Part of the reason why you need a larger piston is that it will maintain fluid/gas displacement at small updown movements.

I am too lazy to write more so I have cut out the below from the King site in regards to Moton Shocks

"Since suspension travels are so small on most modern race cars the MOTON damper compensates for less travel by increasing the diameter of the piston rod, and thus the displacement of fluid. Most damper manufacturers are using a piston rod O.D. of 12 or 14 mm. Using the 22 mm O.D. rod results in about 300% [Fig. 1] mow fluid displacement than usual, making it much more responsive at low damping velocities.

Another advantage of having more fluid displacement is the possibility to combine it with a valve stack which is non pre-loaded and still be able to create enough low speed damping forces. Using a non pre-loaded valve stack results in better tire wear, tire temperatures and traction.

The MOTON piston rods are made from high carbon steel (Chrome Moly for McPherson struts) chrome plated and induction hardened."

My points is that the DMS shocks are truly far superior to the mugen etc shocks, especially since they allow for indept bump/rebound tuning.

Now as to whether they have managed to find a good spring set up is a totally different question:0

 

I agree with the bigger piston size = more fluid movement. That's fine, but you aren't talking about piston sizes with the DMS 50mm, you are talking about piston *shaft* sizes. There's a big difference here. You only need a large diameter shaft on strut type setups. On an application such as the S2000 with double wishbones, a smaller shaft driving a big piston is more than adequate.