Vorshlag Spherical Rear Shock Mount (Pair) - BMW Z3 / E85 Z4 / E30 / E36 / E46 3-Series (M & Non-M)

Description

The factory rubber rear upper shock mount (RSM) for the BMW chassis is a big sloppy rubber ding dong. The wear out over time and are known to be a failure point - and when they fail, they come apart completely. Even when new these have a lot of slop and "slow down" damper reactions to vertical inputs in the shocks. We can fix all of that.

There are three ways to make a rear shock mount for a "pin" style upper shock shaft. The OEM style rubber bushing assembly allows the proper articulation of the shock under suspension movement (it pivots at this mount) but has added deformation that you don't see with a spherical. They can also fail spectacularly. Polyurethane RSMs are too rigid and do not articulate well, causing bind, and this allows unnecessary flexing of the rear sheet metal where it mounts (this area is prone to cracks and breakage when poly mounts are used). Vorshlag Spherical RSMs do a better job than the other two - a metal spherical ball bearing that smoothly articulates with no bind. The metal tolerances are tight, for a slop-free use, which won't delay the damper inputs. Spherical shock mounts are all you see on a race car for good reason, but our design is also applicable to street use - for dual-purpose cars that see some autocross or track time.

Vorshlag RSMs use the largest spherical bearing on the market (19mm ID) - it is massive, which means it is strong. We use a U.S. made, Teflon lined, aircraft quality stainless spherical ball, stronger than the commercial grade import sphericals used in many competitors' RSM designs. The spherical bearing location itself has been raised above the shock tower, to increase overall bump travel for your rear shocks.

UPPER STEM DIAMETER: These shock mounts are designed to work with virtually any rear shock that is made for the BMW models listed. We use different upper and lower bushings (spool pieces) to adapt the big 19mm ID of our spherical bearing to the shaft sizes of the very top of the rear shock.

Vorshlag RSM Upper Reinforcement Plate Kit: We offer a pair of our laser cut reinforcement plates we make as an optional add-on for this shock mount kit with a package savings. These plates sit on top of the shock tower and help sandwich and strengthen the somewhat thin factory sheet metal, above and below. We CNC laser cut these from alloy steel, then added a zinc chromate plating. Our design is thicker and stronger than the factory (Z3) reinforcement plates and a smart move for any street or race car - to help prevent cracked shock towers.

Vorshlag branded products are built to order and most are tailored to match your specific application. Due to the myriad variety of components required for different applications, it is possible that delays can occur in the fulfillment of your order. Please contact us before placing your order if you have a time constraint.