BUY NOW, PAY LATER. Starting at 0% APR 
The ultimate tune for your S58 powered G80 M3 and G82 M4, the JB4 allows you to go from factory stock to full race, and everywhere in between. 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, smartphone integration, electronic wastegate control, ethanol fuel support, and built-in advanced CANbus based diagnostic tools. Installation is easy and completely removable with no splicing or cutting of factory wires.
For the latest performance results, updates, firmware, and map guide be sure to visit N54tech.com.
Wirelessly connect the S58 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 S58 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.
S58 JB4 FEATURES & BENEFITS
• Gains are 80whp/100wtq on pump gas and up to 150whp/175wtq on higher octane or E85 mixtures.
• Improves 0-60 times and 1/4 mile times
• Preloaded with custom JB4 tuning software and up to 8 maps for various fuel and modification levels
• Ethanol (E85) compatible tuning maps
• Able to read/delete fault codes
• View and record up to 40 different gauges/engine parameters in real-time with the JB4 app.
• Boost by gear in 1st, 2nd, and 3rd can be controlled via the JB4 app for a perfect launch
• Compatible with JB4 Mobile for smartphone logging, tuning changes, and adjustment
• The JB4 offers a lot more performance, functionality, and safety than your average performance chip
• Quick Plug & Play Installation
• CANbus OBDII integration offering unrivaled tuning features and performance
• Improved performance over non-integrated chip tunes
• Runs as smoothly as stock, this is how your vehicle should have come from the factory
• Compatible with all driving modes
• Fuel economy unchanged during normal driving
• 91 octane fuel or better required for performance gains
• Not VIN locked and can be removed without a trace and resold down the road
• Includes the rugged JB4 billet aluminum enclosure for protection
• Made in the USA
• Free USA Shipping
• 5 year warranty
S58 JB4 Applications
BMW M3
• 2021+ S58 G80 BMW M3
• 2021+ S58 G80 BMW M3 Competition
BMW M4
• 2021+ S58 G82 BMW M4
• 2021+ S58 G82 BMW M4 Competition
What is a JB4?
The JB4 is a plug & play tune available for turbocharged vehicles. The JB4 tuner installs between your car's sensors and its DME/ECU (computer) and manipulates vehicle performance through these connections making your vehicle much faster. While it's not the only tuning system that operates this way the JB4 separates itself from the competition with much more advanced connection points and processing including CANbus, fuel & spark control, Bluetooth to your smartphone, and a variety of innovative and advanced features not possible with any other system. BMS regularly publishes free mapping and firmware updates adding performance and features as ongoing development allows. In addition, the JB4 system is not VIN-locked to your vehicle and can quickly be removed and swapped between cars or resold at a later time. Often imitated but never duplicated the JB4 has been the gold standard in plug and play turbocharged performance tuning for over a decade. If your looking for S58 tuning for your 2021+ G80 M3 or G82 M4 the JB4 is a perfect S58 engine tune.
Products that have an availability of "In Stock" are shipped same day or the next if ordered before 2 PM EST. Products that have an availability of "Manufacture Ship" are products that ship directly from the manufacture and usually ship within 2-3 business days. At times these items may take longer to ship. By contacting us via our contact form here we can give you an estimate on shipment.
No orders are shipped on weekends or holidays. If we are experiencing a high volume of orders, shipments may be delayed by a few days. If there will be a significant delay in shipment of your order, we will contact you via email or telephone. Please allow additional days in transit for delivery. Please make sure when submitting an order that your address is correct.
Free ShippingFree shipping is available within the lower 48 states for some products. Simply select the free shipping option during checkout, if it's available. (This does not apply to large items or items where shipping quotes are required (ie: bumpers, seats, GT Wings, and so on). Individual items with Free Shipping will be shipped by the carrier of our choice to a single address within the continental United States. This offer excludes shipments going to Alaska, Hawaii, Military Boxes, and items too large to ship via a standard carrier.
Duties and CustomsWhen shipping internationally Complex Seven is not responsible for Duties and customs fee's. These fees must be paid directly to the courier as we do not impose them.
Address RestrictionsThe billing and shipping address must be the same. If it is not we will call or email to verify the inconsistent addresses. This will put a hold on processing your order. If no response from either communication channels, your order will be cancelled and refunded in full.
We don’t ship to PO Boxes.
ReturnsAll returns are subject to re-stocking fee up to 20%. The restocking fee covers the cost of our order processing and restocking process. Items you wish to return MUST be approved prior to your return. Please click here to start the return process. All return inquiries must be sent to us within 30 days of receiving your order. Approved returns MUST be sent back to us within 15 days of receiving your return approval. Returned items must be in brand new condition or, unused condition. Shipping, handling, and transaction fees are non-refundable.
No returns, cancellations, or refunds are allowed on special order items. Once items have been returned to us, and the condition has been inspected and approved, a refund will be issued. Approved refunds are issued within 2-3 business days. Also note that each bank process returns differently, so it might not appear in your account immediately. Exchanges
Please click here to initiate an exchange. Exchanges are subject to second shipping charges unless there was a mistake made on the order. If a mistake was made by Complex Seven Industries, we will provide a return shipping label for you to use to make the exchange as seamless as possible.