Originally Posted by Eric Gebhard

One thing that no one has mentioned is that the shock pistons are quite different from the RRR WCE and the RRR EVO. The front pistons in the WCE shocks are have one 1.3mm hole and and the rears have two 1.0mm holes. On the EVO both the front and rear pistons have two 1.1mm holes. Fortunately the inside diameter of both shocks is the same so you can put the EVO pistons (p/n FM530-3) in the WCE shocks without any problems. One other difference to mention is that the new shock bodies are about 2mm longer than the WCE bodies. How much this affects performance I don't know but it is a difference that should be noted.

If you are thinking about upgrading the shock here are the parts that you will need:

Shock Body p/n FM529-1
Shock Collar p/n VZ109 (this is the servo saver collar)
Piston p/n FM530-3
Front Spring p/n VZ242-4517
Rear Spring p/n VZ243-5017
Shock Ends p/n FM509B (this parts tree has the shock end on it)
Mugen shock ends will also work.