BMW Drivetrain Parts
Ratio Changes - Changing the differential gearing is one of the best and most-effective upgrades you can make on any BMW (old or new). By using a shorter (numerically higher) final drive ratio you are increasing your RPM relative to road speed - this puts you in a more powerful RPM range than before! Since you're in a 'meatier' part of the power band you're now putting down more power/torque to the ground. If you can trade outright top speed for faster acceleration at daily speeds then this is the perfect upgrade for you.
Limited Slip Upgrades - Sadly, many BMWs today are not equipped with a limited slip (posi-traction) differential. BMW has tried to compensate by using traction control that cuts power at the engine or applies the brakes to retard wheel spin (or a combination of both). But nothing beats the function and feel of a a true LSD which may be why BMW continues to use them in M cars. Our LSD upgrades can be done a number of different ways - a factory-type limited slip unit with either 2 or 3 clutch packs, helical type, OS Giken unit, or something truly custom. We can also vary ramp angles and setup to change the limited-slip behavior under acceleration, deceleration, and cornering. Need a custom diff? Call or e-mail to have a quote.
hasmanufactured and supplied high quality lightweight aluminum flywheels to theperformance industry for over 25 years. JB is the original designer andmanufacturer of the BMW E36 aluminum flywheel. JB Racing is constantly expandingtheir flywheel line to include the latest performance applications such as; MiniCooper and BMW E46 325/330, and Z4 utilizing the new 6-speed (SMG) transmission.Â ALL of the current dual-mass replacement flywheels are designed to accommodatemost of the common sprung-hub clutch discs to minimize the gearbox ârattle.âSachs, S.P.E.C., Clutch Net, and others manufacture sprung-hub discs that willclear in the center hub cavity of these flywheels.
All of their flywheels are designed, manufactured, and assembled in-house attheirÂ Florida facility which allows to maintain stringent quality control.You simply cannot buy a higher quality lightweight aluminum BMW flywheelâ¦ atany price!
Flywheels don't last forever. They should be treated like any ordinary wear item. Sachs recommends a new dual mass flywheel (DMF) on every other clutch replacement. There are several indicators for replacing the flywheel: damage to the clutch contact plate (from a severely worn clutch disc), grease leaking from inside (overheating), build-up of clutch material on the contact plate (excessive slipping and overheating), and failure of the internal damping system.
The dampening system uses rubber or coil springs to absorb driveline vibrations. Through age, excessive heat, and aggressive use the rubber loses its resilience and the metal springs lose their strength and become brittle. If the clutch and flywheel have become overheated the internal grease may break down as well. A DMF failure can be massive and catastrophic, not to mention dangerous as bits of metal and rubber fling themselves through the transmission bellhousing. Heat and aggressive driving will accelerate the wear so race and track cars should have their stock flywheels replaced at regular intervals or with any new clutch. Even normal street cars should plan for a new flywheel if it has high mileage.
DMF wear can only be checked with the transmission and clutch removed. If you can rotate the outer flywheel more than 20mm in either direction then it should be replaced.
This is a great upgrade to do at the same time as removing your BMW's clutch delay valve (CDV), a small fluid restrictor fitting found inline of the stock clutch hydraulic line that "slows" the movement of fluid in the system, creating a delay in clutch reaction. Removing the CDV and upgrading to a stainless steel line will make for a noticeable improvement in clutch engagement and overall pedal feel.
The original shifter linkage was engineered with costs in mind. It uses a lot of plastic and stamped sheetmetal parts to keep costs low. But they quickly wear out and by 50,000 miles there is considerable slop and play in the shifter action. UUC Motorwerks has attacked this problem with precision engineered replacement parts that perform better and last longer than the original factory pieces. The DSSR replaces the factory loosely-mounted selector rod with a beefier and more robust milled aluminum piece. The DSSR gives you a more precise and direct feel when shifting. Along with a fresh replacement of the other shifter bushings you won't have that flimsy feeling and side-side slop of a stock shifter linkage (even when new). The DSSR is a great upgrade to any short shifter, or even for refreshing your stock shift linkage.