Description
Unlock the full potential of your Ford Fiesta ST with the JB4 Tuner, the ultimate plug-and-play solution for turbocharged 1.5L and 1.6L EcoBoost® engines. Delivering up to 40hp and 70wtq to the wheels on a stock vehicle, the JB4 improves acceleration, reduces turbo lag, and enhances daily drivability—without the risks associated with ECU flashing.
Discrete, Fully Removable Installation
The JB4 plugs into two easily accessible sensors in the engine bay, working seamlessly with your factory ECU to remap boost, timing, and fueling. Unlike flash remaps, the JB4 is fully removable, leaving no trace when uninstalled. Fuel economy remains unchanged during normal driving, and all driving modes—including spirited driving or track use—remain fully supported.
Advanced CANbus Integration and Safety Features
Equipped with a 64MHz processor, the JB4 samples sensors up to 800 times per second with dedicated 10-bit digital-to-analog converters for precise and smooth tuning. Its fully programmable CANbus system allows real-time monitoring of pedal input, throttle position, engine speed, air/fuel ratio, ignition advance, knock sensors, fuel trims, gear selection, and more.
Safety features include:
- Low boost until oil and water reach optimal temperatures
- Automatic drop to a low-boost map if overheating, knock, lean conditions, or overboost occurs
Multiple Tuning Maps
- Map0: Disable JB4
- Map1: Default +4psi peak over stock
- Maps for 91 octane, 93 octane, E85, stock, and VALET mode
- Boost-by-gear control for improved traction
- Ability to read and clear fault codes
Wireless JB4PRO Connectivity
With the JB4PRO adapter, you can connect wirelessly via Bluetooth 4.0 to iOS or Android devices. The free JB4PRO app allows you to:
- Switch between performance maps
- Record and analyze vehicle tuning data
- Update firmware for free performance enhancements
- Use advanced log analysis tools to diagnose and optimize performance
Performance and Reliability Benefits
- Up to 40hp and 70wtq gains on stock vehicles
- Improves 0-60 mph and quarter-mile times
- Smooth, stock-like operation in all driving modes
- Supports E85 ethanol blends
- Plug-and-play installation with no splicing or cutting
- Not VIN-locked and fully removable
- Logs up to 40 engine parameters
Quality and Warranty
- Durable billet aluminum enclosure
- Designed and assembled in the USA
- 5-year warranty
Vehicle Fitment:
- 2013–2017 Ford Fiesta ST 1.6L I4 EcoBoost® (Mk2)
- 2018–2023 Ford Fiesta ST 1.5L I3 EcoBoost® (Mk3)
Why Choose JB4?
The JB4 has been the gold standard in plug-and-play turbocharged performance tuning for over a decade. By accessing CANbus and sensor data, it provides safe, significant power gains while retaining factory safety systems and leaving your ECU unaltered. Trusted in over 67 countries, it’s often imitated but never duplicated.
