JB4 Tuner for 2016-Present Ford Focus RS & ST

Power gains of up to 50whp and 60wtq to the wheels on a stock Ford Focus 

The JB4 is a plug and play Ford Focus RS/ST tuner that plugs into easy to access sensors in the engine bay and works with your factory ECU tuning to remap your boost, timing, and fueling for optimal performance and reduced turbo lag. It features a 64mhz processor allowing sensors to be sampled 800 times per second using dedicated 10-bit digital to analog converters, ensuring smooth and powerful performance.  

Unlike other tuning systems, the JB4 includes a fully programmable CANbus system, upgradable firmware, and data logging capability. CANbus allows the JB4 to take into account pedal input, throttle position, gear, engine speed, air/fuel ratio, fuel trims, ignition advance, knock, and many other factors and incorporate those into the performance mapping. It can also read/delete fault codes, and includes unique safety features such as keeping boost pressure low until oil and water is up to temperature to provide proper engine and turbo lucubration and drop to a low boost map if the engine starts to overheat, run lean, excessively knock, or over boost. 

The JB4 offers a lot more performance, functionality, and safety than your average performance chip.

The default JB4 map 1 runs 4psi over stock peak, and tuned maps, including stock and valet mode, can be selected on the fly using a BMS diagnostics cable or JB4 mobile smartphone adapter. 

Installation is very discrete, and it quickly removes without a trace when needed. Includes maps for 91 octane, 93 octane, and E85 (ethanol fuel) mixtures. Fuel economy during normal driving is unchanged. Compatible with all driving modes. Made in USA. 5 year warranty.

Wirelessly connect the JB4 to your Bluetooth 4.0 compatible iOS and Android device via the JB4 Mobile connect kit or to your Windows laptop with the BMS data cable. Both options allow you to record and analyze vehicle and tuning data, change JB4 performance maps, and update JB4 firmware as we release free newer versions with updates, more powerful maps, and new features under development. A separate JB4 Mobile app purchase is also required.

The items installed or applied to vehicles are intended strictly foroff-road use onlyandtrack vehicles. These modifications may not comply with emissions, safety, or environmental regulations required for public road use underEnvironmental Regulatory Agency (ERA)laws. It is the sole responsibility of the vehicle owner or operator to ensure adherence to all applicable local, state, and federal regulations. Use on public roads may result in legal penalties or vehicle impoundment. Always verify compliance with local authorities before installation.

We get a large number of custom orders and requests everyday, so as a result it is not always possible for us to keep every item in stock at all times in our warehouse. If you require the item urgently please contact our sales team here to check the stock before you make your purchase.

If you're unsure whether a part will fit your vehicle, feel free tocontact us herewith your inquiry. Our helpful sales team will reach out to confirm if it's the right match for you.

We offer a flat-rate shipping fee across thecontinental United States. This excludes Alaska, Hawaii, and U.S. territories. For international orders, additional shipping costs will apply. Please contact us for a quote if you are outside the continental U.S.

Also, feel free to also contact us at ColoradoN5X@Gmail.Com for any other questions.

Not all items are covered by warranty. Items including warranty, will clearly state that there is warranty within the product description. Most of these items will be a standard 1-year warranty against manufacture defects. You, the customer, will be responsible for shipping and handling. We will fix/replace that item with a product that is in working condition if you meet the warranty criteria. Please note that you will be allowed ONLY 1 claim within the year for that product. ColoradoN5X is not responsible for any damage caused during the installation of our products.