BMW 335d Engine ECU RemapThe BMW 335d Engine is already a very good engine in factory form, however there is so much more potential to be released from the 335d through ECU remapping.
The BMW 335d uses a Bosch EDC16 Engine ECU which is flash programmable via the OBD diagnostic socket in the passenger compartment. This means the ECU does not need to be removed from the car and the process can be completed either in-house or using our ByteFLASH handheld OBD programming solution anywhere in the world.
We spent many months of development work on our BMW 335d ECU remap software. Careful changes are made to injection timing, duration, torque limiter maps plus turbo pressure and limiter maps to safely release gains of +55bhp and +120Nm of torque whilst also offering a smooth drive, much wider power band and improved throttle response. The 155mph factory speed limiter can also be removed from the engine ECU during a remap.
Too many times we've seen BMW 335d remaps which are sub-standard arrive at our premises with at best inferior power and at worst either too much turbo pressure or sky-high fuel rail pressure, both of which can cause expensive engine failures. All of our 335d remap software is safe for a standard car. We do not use any additional rail pressure and additional boost pressure is minimal at 10% above factory at peak, yet through careful modification of other parameters we still achieve one of the most economical and powerful 335d tuning files available.
BMW 335d Gearbox TCU RemapThe BMW 335d Automatic Gearbox can also be improved by remapping the gearbox TCU. The gearbox TCU (transmission control unit) is essentially another ECU, very similar to the engine ECU but this one controls the automatic gearbox.
The problem with only remapping the Engine ECU on the BMW 335d is the gearbox also has electronic torque limiters in place which prevent us from getting maximum performance and economy gains from engine tuning alone. Again, as with the engine, the gearbox TCU on the 335d is programmable via the OBD diagnostic socket, which makes this process nice and easy for the end user. Performance gearbox software can be despatched for delivery worldwide with easy installation, or installed at our premises.
The BMW 335d gearbox remap we have developed offers the following benefits:
Earlier torque convertor locking provides a more 'connected' and less 'slushy' feel traditionally associated with automatic transmissions. It also provides efficiency improvements by transmitting a higher percentage of the engines power to the wheels earlier. This has the additional added benefit of hugely increasing off-the-line performance.
BMW 335d Dyno GraphWe tested our 335d software extensively on a dyno to achieve the best results. The graph below shows stock runs, power from our economy/performance blend and from our performance maps. All power is quoted at rear wheel horsepower, as its at the wheels where a dyno measures power. Based on usual drive-train losses these figures equate to 50bhp and 110Nm gains on our test vehicle.