Why in the world would you need a heavy duty transmission brace for an E46 M3, especially for a 5-speed conversion?
Rogue Engineering has developed a replacement transmission brace for the E46 M3, made from 3/16" CRS that is CNC plasma cut and CNC bent. This incredibly strong brace is available in two powdercoated finishes, black and red. It's also AER
This brace allows for the factory dual-pipe exhaust to travel under the transmission like stock, as other transmission brace alternatives (the factory M54) are too thick as they are made from cast aluminum. The low profile of the Rogue Engineering brace allows for the clearance necessary for the exhaust to clear without interference.
A popular conversion for E46 M3 track-only/racecars is swapping out the factory 6-speed transmission for a 5-speed from an E36 M3 (or E46 330). Why may you ask? There are many reasons why people are doing this:
- Lighter weight, 40 lbs. lighter than the factory 6-speed transmission
- Cheaper replacement costs. 5-speed transmissions can be had for around $400 at automotive recycling centers (junkyards).
- Near identical gearing internally (1st through 5th). No need for 6th gear (overdrive) at the track
- Clutch choices are plentiful (the 5-speed uses a 1-1/8" 10-spline clutch disc)
Modifications to the factory E46 M3 driveshaft are easy for any professional driveshaft shop, as they add 3.7" of additional length before the center support bearing (which should be changed as a maintenance item). Of course, the appropriate shifter should be ordered for this change, as the factory shifter mechanism is not longer compatible.