Unlock serious performance from your Subaru 2.4 litre turbo with the JB4 plug and play tuner. This advanced piggyback ECU upgrade delivers gains of up to 50 hp at the wheels on a stock car running pump fuel, with even greater potential on ethanol blends and with supporting bolt-ons. Available from Nforcd, it is a powerful yet reversible tuning solution that keeps factory safety systems intact while offering smartphone control and extensive data logging.
- Up to 50 hp to the wheels on a standard vehicle on pump fuel, with higher gains on ethanol mixes and bolt-on upgrades
- Simple plug and play harness for quick install and easy removal
- On the fly map switching from your phone or tablet between stock and performance maps
- Preloaded with custom JB4 Subaru software and up to 8 maps for different fuels and modification levels
- Ethanol E85 compatible tuning maps
- Boost by gear control for improved traction in lower gears
- Built-in data logging plus read and delete fault codes
- Progressive water methanol injection support
- CANbus OBDII integration for smooth factory-like drivability, advanced safety and superior control
- View and record up to 30 live engine parameters via the JB4PRO app
- Compatible with all driving modes and fuel economy unchanged during normal driving
- Not VIN locked and removable without a trace, ideal for resale or transferring between vehicles
- Rugged billet aluminium enclosure, designed and assembled in the USA
- 5 year warranty and firmware updates available
- 91 octane fuel or better required for performance gains
Wireless control with JB4 PRO
Pair the optional JB4 PRO Bluetooth connection to your iOS or Android device to change maps, log and analyse data, and load firmware updates using the free JB4PRO app. The compact adapter sits inside the JB4 enclosure for tidy installation and added weather protection.
How the JB4 works
The JB4 installs between the engine sensors and ECU, using CANbus data to safely adjust boost, timing, air fuel and fuel trims to deliver strong, smooth power gains similar to an ECU flash yet without unlocking or flagging the ECU. It retains factory safeguards and offers features not possible with basic chips. Nforcd knows this system well and it has been a popular choice with our customers looking for a reversible, high-performing tune.
Vehicle fitment
- 2022+ Subaru WRX 2.4L 4 cylinder turbo
- 2019+ Subaru Ascent 2.4L 4 cylinder turbo
- 2020+ Subaru Legacy XT 2.4L 4 cylinder turbo
- 2020+ Subaru Outback XT 2.4L 4 cylinder turbo
Order your JB4 tuner from Nforcd today for a proven, feature-rich performance upgrade and seamless daily drivability. Professional fitting is available at Nforcd in Warwickshire. To request a fitting quote, email Sales@nforcd.com.