Frequently Asked Questions

Will it void my warranty? Should I remove parts before going in for service?
Most leave parts like ECU tunes and intakes on for basic oil changes and service but we suggest removing any modifications prior to making a warranty claim. This is to ensure they are not causing the problem and to make things easier for your technician who may not be familiar with how to properly remove and reinstall your modified parts. Before going in we also suggest reading/deleting the hidden DME codes using the JB4 built in code reading/deleting, a CAN Tool, or a BT Cable. JB4 users should always set the tune to map 0 / pass through mode before going in to avoid it interfering with external diagnostic equipment.

Should I get a DME reflash or the JB4?

The JB4 offers unique advantages not found in flash tunes including on the fly steering wheel control map switching, an optional in dash boost gauge and shift light, auto tuning to ensure you always have the safest and most powerful tune for your particular conditions and modifications, built in code management, optional race gas and higher performance mapping, methanol integration, and for more advanced users a full user adjustable tuning interface. For those with leased vehicles or under factory warranty the JB4 offers the ability to be removed without a trace. While flash tuning leaves behind a permanent record of maximum RPM, load/boost target, vehicle speed, etc, that can never be deleted piggyback tuning on the other hand ensures the DME never sees anything other than the original factory tuning values. With its full CANbus integration the JB4 has access to every piece of information the DME does and thus can provide factory smooth mapping with reduced turbo lag and much stronger power outputs. It's truly how the vehicle should have come from the factory. In addition the JB4 is generally half the price of flash tuning.  

What is the difference between the JB+ and the JB4?
The JB+ features a faster install and does not require you to touch the ECU. The JB4 is a more robust system including steering wheel control map switching, direct boost solenoid control, throttle position mapping, and many other additional features that allow it to produce a lot more power. On average the JB+ gives 40hp to the wheels, while the JB4 gives 70-80hp to the wheels, on an otherwise stock car. The JB4 tuned car will also have less lag and also include built in hidden code reading/deleting. The JB+ requires the optional CAN Tool or BT cable for hidden code management.

Why doesn't the JB4 include a 155mph speed limiter removal?
While "clamping" the hardwired speed signal to the ECU as piggybacks do will allow the vehicle to exceed 155mph, the true vehicle speed is recorded by the stability control module and other modules using sensors at each of the four wheels. These modules will always contain the true vehicle speed regardless of the ECU clamp. For those customers who are out of warranty and fully aware of the extreme risks and danger in operating their vehicle in excess of 155mph on race tracks, BMS offers a stand alone speed delimiter that plugs in to the JB4 harness.

I'm interested in an intake, but won't the exposed filters just suck in hot air?
The short answer is yes, they will ingest hotter air, but a lot more of it. The end result is actually cooler air entering the engine. This is because you are reducing the huge pressure drop across the factory airbox, dramatically improving the efficiency of the compressors. The BMS intakes also significantly reduce impeller speed improving turbo reliability.

Wouldn't it be best to have an open element filter ducted to fresh air?
The short answer is yes, but the devil is in the details. With the packaging requirements of the N54 motor most "cold air intakes" use an inadequate 3" piping ducted to a single filter in the fender. In addition to being too small to support higher power levels, the additional bends and twists reduce intake flow resulting in suboptimal top end performance. After months of testing various hot and cold designs, including various heat shields, we feel the BMS intakes offer the best blend of performance and value. They are used on the worlds most powerful N54s.

Are the JB tuners compatible with my automatic transmission?
Yes! Not only is the JB compatible with the automatic transmission, but the automatic N54s are generally faster than their manual equipped counterparts when it comes to straight out acceleration. Manuals tend to do better on the road courses though.

Are the JB tuners compatible with my Xdrive equipped vehicle?
Yes! In fact BMS has several Xdrive customers running in the 11s. The extra torque really wakes the heavier Xdrive system up, and the additional traction makes for a great combination.

Are JB and Power Box tuners compatible with exhausts, intakes, blow off valves, and other modifications?
Although no additional modifications are required the JB and PBX tuners are compatible with all intakes, exhausts, intercoolers, and BOV/DVs. No additional or special tuning is required as boost, timing, and air/fuel systems are fully closed loop.

How long will my order take to get here?
2-5 business days in the United States and 4-10 business days world wide. Orders are generally shipped USPS, United States Postal Service, or EMS internationally.

BMW Paddle Shift related FAQ?
Located at the bottom of the paddle shift page. (click here)


 

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