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Shipping’s on Us for Select Products
Christmas Sales: Up to 20% Off Selected Brands
Listing New Feature: OE Reference Numbers
New Brands Now Available – VEMO, VAICO & ACKOJA!
New Arrivals from Powerflex!
New Powerflex Transfer Case Bush Insert!
New Forge Arrival
New Arrival: Precision Raceworks Auxiliary Fuel Systems
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Christmas Sales is here — and it’s bigger than ever. Get 20% OFF with code XMAS20 on your next order and stay tuned as we reveal new products every week leading up to the main event. From performance upgrades to styling and maintenance essentials, this is your chance to score the best deals of the year.
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OE Reference Numbers – Easier, Accurate Part Matching!
Quickly find the right parts for your car with OE reference numbers.
Now available on all listings!
Now available on our website! Meanwhile don’t miss out – click below to explore our ongoing 2025 Sale and grab unbeatable deals.
We’ve just added three new products to our lineup:
Upgrade your ride with these high-performance rear lower toe link inner bushes, designed for improved handling and durability. Available now!
Upgrade your drive with our latest Powerflex Transfer Case Bush Inserts, designed specifically for the E9x, X1 E84, and X3 E83 models. These easy-to-fit inserts fill the void in the OE rubber bush, reducing movement, enhancing stability, and prolonging the life of your bush.
Choose the perfect fit for your setup:
Perfect for maintaining performance and reliability, these inserts are a must-have for any enthusiast. Shop now and experience the difference!
New Arrival Alert!
Unleash the full potential of your BMW B58 engine with the Forge BMW B58 Carbon Induction Kit!
Highlights:
Optimize performance, reliability, and style in one sleek package. Get yours now!
Take your X3M, Supra, and M2 to the next level with Precision Raceworks’ Auxiliary Fuel Systems (AFS). Designed for stability and performance, these systems deliver unmatched fuel control for your port injection setup.
Why Choose Precision Raceworks AFS?
Key Features
Available Now:
Upgrade today for unmatched fuel performance!
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BMS
Price Match Guarantee
If you find a lower price at an eligible UK retailer website, we will match it.
Fitting service at Xatrix, West Yorkshire
We can offer a fitting service for this part. Contact us for a fitting quote.
The ultimate tune for your S55 powered vehicle, the JB4 allows you to go from factory stock to full race, and everywhere in between, with the push of a button on your steering wheel. The JB4 installs and removes easily and includes many unique features not found in any other tune including user adjustable 1st and 2nd gear boost limiting, map switching in dash, electronic wastegate control, ethanol fuel support, and built in advanced CANbus based diagnostic tools. Installation is completely removable with no splicing or cutting of factory wires.
You may also wish to add the Data Cable or the Bluetooth Connect Kit for additional features.
For the latest performance results, updates, firmware, and map guide be sure to visit N54tech.com.
JB4 Map Guide
Map 0: Disable JB4 / Full Pass Through Mode
Map 1: Stage1 map adding approximately 40whp and 40wtq across the power band on pump gas. Suitable for all stages and fuel mixtures.
Map 2: Slightly more aggressive version of map 1 intended for vehicles with exhaust modifications and 93+ octane fuel. Can also be used with E85 and racing fuel mixtures.
Map 3: Slightly less aggressive version of map 1 intended for vehicles running on lower grade fuels such as 91 octane.
Map 4: OEM performance but with JB4 active for diagnostics only.
Map 5: //M low torque / linear throttle map.
Map 6: Custom tuning map.
Map 7: Race gas map. Requires 100 octane unleaded fuel and for the fuel mass connector to be installed. This map can also be used with up to 35% E85.
Map 8: Methanol injection map. Requires BMS FSB controller or methanol kit for progressive mapping and safety systems.
2018+ F87 LCI M2 Competition (S55)
2020+ F87 LCI M2 CS (S55)
2014+ F80 M3 (S55)
2014+ F82 M4 / M4 CS (S55)
F-S55-JB4
Manufactured by
Burger Motorsports
Warranty
5 Year BMS Repair Warranty

JB4 Optional Phone Software
Change maps on the fly
JB4 S55 CAN Flap DEMO

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