UUC's Ultimate Short Shift kit for the E46 3 series
There is a reason UUC's Ultimate Short Shift Kits are some of the most popular upgrades for street driven BMWs...
Ask around, they are the best.
Smooth and tight, the Evo 3 line of SSKs are a favorite of enthusiast everywhere. Its our personal opinion that this is the best E46 shifter kit for sale at any price- not just because the shift throw is reduced; but because of the increase in the precision feel and smoothness of the shift.
From UUC Motorworks:
The UUC Ultimate Short Shifter is unique, completely different than anything else available. Our design starts with the finest materials: T-304 stainless steel, T-6061 aircraft-grade aluminum, precision bearings, self-adjusting and lubricating primary pivot bearing, and the finest-grade silicone vibration absorbing material. Our products are not modified BMW components, and they are not "one size fits all" as with lesser offerings.
In the interest of continually improving our product, we are always developing and testing modifications intended to bring "ultimate" to higher levels. With that in mind, our latest generation brings the BMW shifter to a new level of smoothness and minimized shift effort.
The unique characteristics of the design include:
* Height adjustment via upper-section length change (this does not change linkage geometry like moving-ball designs).
* Flex and rotation-free lever construction with full-length vibration-absorbing bushing.
* Linkage geometry perfectly corrected, with self-adjusting primary pivot bearing that permanently retains lubrication and precision (most models).
* Zero-tolerance lower pivot bearings that never require lubrication and eliminate significant mechanism friction. These do not wear or ovalize like solid-metal or plastic designs with expanding tolerances.
UUC's optional 'Double Shear Selector Rod'
The goal.
While producing a "short" shifter, our more important goal in improving the BMW shifter assembly is to increase the precision and smoothness of the overall operation.
The problem.
One significant wear area that has never been addressed previously is the wear and ovalization of the linkage connection points at the transmission and the shifter's lower pivot. (figure 1)
In the original BMW design, the connection at both ends has a large injection-molded plastic bushing. We already know how badly plastic wears in an automotive application, and these areas are not an exception. The design of the selector rod has a pin at 90° to the main rod, which exerts a tremendous amount of leveraged force on the selector joint bushing from one side (known as a single shear force). The result is a steady deformation of the bushing, resulting in looseness and slop in the entire mechanism. (figure 2) The fig. 2 image shows a selector joint that has approximately 25K miles of use.
The looseness and slop are magnified by the leverage-multiplication effect of the shift lever itself. The result is an in-gear shifter "free play" of 3/4" and up to 1" in either direction, over 35mm total. (figure 3)
The cure.
A temporary fix is to simply replace the selector joint. Unfortunately, this is only a temporary fix as the new joint's bushing will exhibit the same rapid deformation. To permanently fix this, a change in the fundamental design of the pivot is required, changing the assembly to a double shear system with the UUC Double Shear Selector Rod (DSSR). (figure 4 and 5)
The DSSR redistributes the torsional forces from the pin/bushing interface to the complete face area on both sides of the selector joint. (figure 6) By taking advantage of the strength of steel in the DSSR and the body of the joint, the problem of deformation is eliminated and the movement of the selector rod correlates directly to movement of the selector joint - the only "free play" movement remaining in the shifter assembly is from within the transmission itself. (figure 7) In-gear "free play" is reduced to approximately 10mm total when used with a UUC EVO3 shifter. (figure 8)
The original BMW shifter and all other aftermarket shifters (except UUC which uses deformation-free bearings) contain a plastic bushing similar to the selector joint, and the exact same wear and ovalization causes those shifters to get sloppy. The DSSR permanently fixes these shifters also. The DSSR is compatible with all brand shifters, whether original BMW or other-brand aftermarket. When used with the original BMW shifter or other aftermarket shifters, the amount of "free play" will be greatly reduced but varies by shifter (flexation of the shifter shaft contributes to the total "free play" travel).