Group 18: JB4 for EA888 Gen4 for Mk8 Golf R, Audi S3 8Y, Cupra Leon/Formentor

The JB4 is a true user adjustable plug and play solution. Power Gains: Starting at peak 370bhp and 380ft lb.

The JB4 features CANbus connectivity for more advanced tuning, direct AFR control, advanced safety systems for boost, air/fuel ratio, fuel trims, and engine knock, boost mapping by gear for improved traction, integrated water/meth control, and much more. 

The unit can be used with our JB4 Bluetooth Connect kit providing for full in-car engine parameter display, map switching, and adjustment.

Stored maps available for 91/95ron and 93/98ron for manual and DSG

JB4 Features & Benefits

• Up to 75hp on a stock vehicle, 50hp/65ft lbs on 91/95ron and 65hp/70ft lbs on 93/98ron
• Improves 0-60 times and 1/4 mile times
• Preloaded with custom tuning software and up to 8 maps for various fuel and modification levels
• The JB4 offers a lot more performance, functionality, and safety than your average performance chip
• Quick Plug & Play Installation
• CANbus OBDII integration offering unrivaled tuning features and performance
• Improved performance over non-integrated chip tunes
• Runs as smoothly as stock, this is how your vehicle should have come from the factory
• Compatible with all driving modes
• Fuel economy unchanged during normal driving
• Compatible with JB4 Mobile for smartphone logging, tuning changes, and adjustment
• 91 octane fuel or better required for performance gains
• Able to read/delete fault codes
• Not VIN locked and can be removed without a trace and resold down the road
• Made in the USA
• Free USA Shipping
• 5 year warranty

Vehicle Fitment

What is a JB4?

The JB4 is a plug & play tune available for turbocharged vehicles. The JB4 tuner installs between your car's sensors and the DME/ECU (computer) and manipulates vehicle performance through these connections making your vehicle much faster. While it's not the only tuning system that operates this way the JB4 separates itself from the competition with much more advanced connection points and processing including CANbus, fuel & spark control, Bluetooth to your smartphone, and a variety of innovative and advanced features not possible with any other system. BMS regularly publishes free mapping and firmware updates adding performance and features as ongoing development allows. In addition, the JB4 system is not VIN-locked to your vehicle and can quickly be removed and swapped between cars or resold at a later time. Often imitated but never duplicated the JB4 has been the gold standard in plug and play turbocharged performance tuning for over a decade.