Adjustable pinion snubber

When properly adjusted according to the Race Bulletin above, the rear suspension essentially stops compressing except for the rear spring segment resulting in a very stiff ride. Brutal is probably a better word for it.

They are great for launching on a smooth track, but brutal on the open roads. CalTracs are much the same. I just can't take the rough ride they leave you with any more, and had to find other ways to plant the tires on launch.