JB4 OR FEMTO WHICH IS BETTER FOR ME?

"To be used for OFF-Road use only"

JB4

The JB4 is a piggyback tuning device that modifies the signals going to the engine's ECU to optimize performance. It sits between the sensors and the ECU, intercepting and adjusting signals to increase horsepower and torque without directly modifying the ECU software.

Benefits of JB4:

1. Ease of Installation and Removal: The JB4 is plug-and-play, meaning it can be easily installed or removed without altering the vehicle’s stock ECU software. This makes it a great option for those who want temporary performance gains without permanent changes.
2. Adjustable Maps and User Control: The JB4 offers customizable maps and user control, allowing drivers to adjust performance settings according to their needs, such as for fuel economy or maximum power.
3. CEL Lights: Unfortunately some vehicles will show a CEL light on the dash when downpipes are installed. There is nothing we can do to turn off the CEL light.

JB4 for the B58  |  JB4 for the S58  |  JB4 for other BMW

FEMTO

The FEMTO unlock service is a process where the factory ECU is unlocked, allowing for full flash tuning. This unlock allows tuners to directly access and modify the ECU’s software, which is required for performance enhancements.

Benefits of FEMTO Unlock ECU:

1. Full Access to ECU Parameters: Unlocking the ECU provides tuners with full access to the car’s software parameters. This allows for more precise and extensive tuning options, optimizing engine performance beyond what a piggyback (Fancy Boost Controller) device can offer.
2. Increased Performance Potential: With a FEMTO unlock, you can achieve higher power gains because the tuning can adjust more parameters, such as fuel mapping, ignition timing, and boost control, for optimal performance.
3. Compatibility with Advanced Tuning Platforms: An unlocked ECU is necessary for using advanced tuning software like bootmod3, MHD Tuning, and others. These platforms offer more features and fine-tuning options, including custom maps and diagnostic tools.

The FEMTO process takes about 10-14 business days. We send out ECUs weekly to Europe. For local customers we offer the option to clone your existing ECU so your vehicle is not immobile while the FEMTO process is being conducted. ie: "Purchasing an extra ECU".

If your vehicle is a 2024, send us your vin # to check if Unlock is available.

Conclusion:

The JB4 is ideal for users looking for a simple, non-invasive performance upgrade with the flexibility to revert to stock settings easily. Meanwhile, the FEMTO unlock ECU is suited for those seeking maximum performance and full control over the tuning process, although it requires a more permanent modification to the car’s software.

Ethanol Fuel Mixtures (E85 - E50 - E30)

E85 fuel mixtures can also be used by utilizing the FUEL-IT kit for either the JB4 or FEMTO Unlocked ECU.

FUEL-IT Flex Fuel Kit for the S58 G8X