BMS JB4 Tuning Box for BMW N55 E82 E84 E90 E92 E88 E91 E93 E70 E71 (135i 335i X1 X5 X6)
Unlock serious power and torque from your BMW N55 with the Burger Motorsports JB4. This plug and play piggyback ECU tuner is the proven, map-switchable performance upgrade for E Series BMW 135i, 335i and X1 owners who want faster 0-60 times, stronger midrange, and a properly integrated tuning solution. Expect gains of up to 60 hp and 60 lb-ft at the wheels on a stock car, and as much as 100 whp on a fully modified setup, with smooth OEM-like drivability, CANbus OBDII integration, and unrivalled safety features.
At Nforcd we have fitted and run the JB4 on our own cars and for many happy customers. The results speak for themselves: sharper throttle response, harder acceleration, and repeatable performance you can rely on day in, day out. If you are searching for BMW N55 tuning, BMW 135i tune, 335i tune, X1 tune, E Series BMW tuning box, JB4 tuner, or a remap alternative, this is the upgrade you have been looking for.
Why choose the JB4 for your BMW N55?
- N55 power gains of up to 60 hp and 60 lb-ft at the wheels on a stock vehicle
- Up to 100 whp potential on fully modified cars with supporting hardware
- Improves 0-60 mph and quarter mile performance
- True plug and play installation with model-specific harness
- In-dash on-the-fly map switching between factory and performance maps
- Optional in-dash gauge hijack for boost and critical parameters
- Progressive water/methanol and ethanol (E85) compatible tuning maps
- Built-in CANbus OBDII integration for advanced control and safety
- Reads and deletes fault codes
- Runs as smoothly as stock and works with all driving modes
- Fuel economy unchanged during normal driving
- Compatible with JB4 Mobile for smartphone logging and adjustments
- 91 octane or higher recommended for performance gains
- Not VIN locked, removable without a trace, and resellable
- Rugged billet aluminium JB4 enclosure
- Made in the USA with a 5-year BMS repair warranty
No previous stages or additional mods are required to enjoy the JB4. Simply install and go. For advanced users, add the optional BMS Data Cable or Bluetooth Connect Kit for laptop or smartphone logging, map updates, and fine tuning.
Optional Add-ons
- BMS Data Cable for laptop connectivity, data logging and firmware updates
- Bluetooth Connect Kit for JB4 Mobile app smartphone control and logging
Vehicle compatibility
BMW 1 Series
- 2010-2013 N55 BMW E82 E88 135i
BMW 3 Series
- 2010+ N55 BMW E90 E91 E92 E93 335i / 335ix
BMW X Series
- 2011+ N55 BMW E84 X1
- 2011-2013 N55 BMW E70 X5 35i / 35ix
- 2011-2013 N55 BMW E71 X6 35i / 35ix
Harness selection: A or B
Your N55 may require Harness A or Harness B. Please reference the image below to identify the correct harness for your car, or contact us for help.
What is included
- E Series N55 JB4 control unit in billet aluminium housing
- Model-specific JB4 wiring harness
- RHD Extension Harness Upgrade
- BMS Data Cable (optional)
Installation and fitting
The JB4 installs with a straightforward plug and play harness. No cutting or splicing required. Download the official install guide and be up and running quickly.
Prefer professional fitting? Nforcd offers expert JB4 installation and setup in Warwickshire. Email Sales@nforcd.com for a fitting quote and availability.
Compatibility check before dispatch
To ensure the correct part for your vehicle, we run a compatibility check prior to dispatch. Provide your UK registration number or the last 7 digits of your VIN at checkout.
Part numbers
- E-N55-JB4-A (Harness A)
- E-N55-JB4-B (Harness B)
Warranty and manufacturer
Manufactured by: Burger Motorsports
Warranty: 5 Year BMS Repair Warranty
Dimensions and weight
- E-N55-JB4-B (Harness B) approximate dimensions: 26 x 16 x 6 cm
- E-N55-JB4-B (Harness B) approximate weight: 525 g
Dyno and videos
JB4 Optional Phone Software
JB4 135i 335i Steering Wheel Controls Demo Video
JB4 Optional In Dash Boost Gauge / Shift Light Demo
JB4 Optional Startup Gauge Sweep
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