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Terry @ BMS Terry @ BMS is offline
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Default E Chassis N55 MHD Back End Flash Maps - 10-24-2016, 07:31 PM

Use subject to terms and conditions posted at

THIS PART IS LEGAL FOR USE ONLY IN COMPETITION RACING VEHICLES AS DEFINED UNDER CALIFORNIA LAW, AND IS NOT LEGAL FOR USE IN ANY OTHER MOTOR VEHICLE. California law defines a "racing vehicle" as "a competition vehicle not used on public highways." (Calif. Health & Safety Code 39048) This part may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event. Competition-only motor vehicles may not be driven to a racing event on a public highway and must be transported on a trailer or other carrier. USE OF THIS PART IN ANY OTHER VEHICLE MAY SUBJECT YOU TO FINES AND PENALTIES FOR VIOLATION OF FEDERAL AND/OR STATE LAW, WILL VOID YOUR WARRANTY FROM BURGER MOTORSPORTS, INC, AND CAN VOID YOUR VEHICLE'S WARRANTY. It is your responsibility to comply with all applicable federal and state laws relating to use of this part, and Burger Motorsports, Inc hereby disclaims any liability resulting from the failure to use this part in compliance with all applicable federal and state laws.

Suggested Flashing Cable:

Hey guys,

We'll use this thread as the central point of information for our E series N55 MHD back end flash maps.

What is a JB4 BEF?

Back end flash are maps you load on to your DME that are specifically meant to be run with a piggyback system. These maps work with the JB4 piggyback to adjust fueling, timing, VANOS, speed delimiter, and other functions on the flash side while allowing the JB4 to retain its superior absolute boost control, on the fly map changes, in dash gauges, shift light, wastegate and fuel trim auto tuning, ethanol autotuning, gear dependent boost control, JB4 mobile wireless data logging, methanol/port injection control, advanced over boost, run lean, engine knock safety systems, etc, etc. It's simply the best of both worlds.

And the JB4+BEF virtually eliminates the need for time consuming and expensive custom tuning. It's so easy to dial in we provide free tuning support via the N54Tech support forum.

For the E series N55 platform BEF maps are loaded via the MHD flashing system which runs on android devices using a universal DCAN to USB cable. While BMS provides unlocked BEF map templates free of charge there is a ~$199 charge imposed by MHD per VIN to use their flashing system. Once the VIN is registered by MHD maps can be loaded, unloaded, and changed as many times and as often as you'd like.

Once installed and the JB4 is set to BEF mode (option 4/2 in dash) the boost targets on each map will change to higher boost absolute maps designed specifically for use with BEF maps. For example map1 goes up to 16psi peak, and map2 goes up to 19si peak.

What are the benefits of running a JB4 with a flash rather than flash only for tuning?

While it's possible to tune an N54 without a JB4 doing so comes with many disadvantages.

1) The JB4 includes more robust safety systems than are possible via flash only. Starting with fundamental safety systems like reverting to a safety map if boost exceeds your safety setting, if the air/fuel ratio in either bank turns dangerously lean, or if fuel pressure drops below a safe level. While you might think the DME alone can handle these basic safety systems surprisingly it's not the case. The DME will happily let you run along at full power and a 18:1 AFR, with boost pegged if a WG line drops off, and the only fuel pressure safety provided is when fuel pressure drops down so low fuel injection itself has to be suspended. In addition to these basic safety systems the JB4 offers layered advanced safety systems. For example it monitors fuel trims bank to bank and reverts to safety if they exceed more than a 15% variance indicating a possible fuel distribution or o2 sensor issue. Port injection and WMI add extra failure points and the JB4 control provides advanced safety systems for them as well. The port injection FAQ covers the basics.

2) The JB4 boost control system is programmed as absolute meaning you'll always target a specific boost level. Unlike the DME which naturally implements a LOAD control system where boost levels go down when it's cold and go up when its warm. The opposite of what you generally want for turbocharged performance. In addition the JB4 is quick and easily adaptable to a wide range of setups eliminating the need for expensive custom boost tuning and the risks that come with repeated logs on systems that are not yet setup. It's not uncommon for engine damage to occur while a new setup is initially being dialed in. The JB4 automatically tunes wastegate dutycycle, fuel trims, and other important tuning criteria full time in the background greatly simplifying the tuning process. In addition the JB4 auto-tuning map can self tune for various ethanol mixtures without the need of an expensive and difficult to install flex fuel sensor. Pedal to boost mapping, spool aggression, boost by gear, and other critical factors can be easily adjusted in dash on the fly to suit the needs for the particular track or racing situation.

3) On the fly changes. Whether it's changing the boost/power level, boost by gear setting (including being able to disable it on the fly for burn outs or if traction turns out to be better than expected), pedal input, or what gauges are shown in dash, the JB4 allows a wide range of user adjustment real time from the drivers seat without having to use a 3rd party device or risk programming the DME between runs.

4) The JB4 allows for much better real time feedback to the driver. User adjustable in dash gauges allow you to keep a constant eye on boost, timing, knock, meth flow, and/or AFR, all selectable and changeable on the fly from the drivers seat. A user adjustable shift light can be triggered making rowing through the gears easier. JB4 Mobile allows wireless bluetooth logging via your Android or Apple phone without a cable locked in your OBDII port. In addition you can select map0 on the fly to allow OBDII port logging and diagnostics when needed for vehicle service. The JB4 default logging set includes all relevant data required for tuning including boost, timing cylinders 1-6, AFR and fuel trims in both banks, high and low fuel pressure, load, calculated torque, trans temperature, and many other parameters. The JB4 provides a simple to use but incredibly robust data logging system eliminating the need to select what parameters to record before each run and providing instant on the fly charting without the need of 3rd party internet programs. We routinely add parameters to the JB4 logging set based on customer feedback and evolving tuning requirements. The JB4 samples boost and analog sensors 250 times per second and CANbus specific data like air, fuel ratio, fuel trims, and timing advance 10 times per second.

5) Integrated JB4 features such as port injection control, flex fuel sensor, and progressive water/meth (WMI) control eliminate the need for independent add on boxes that are more difficult to install and technically unable to communicate with each other. Integration allows these extra features to share information for a smooth and cohesive tuning solution. For example with the JB4 NLS and JB4 port injection control when you press the clutch in for NLS your port injection flow is momentarily suspended to avoid huge backfires that have been known to blow out o2 sensors and in extreme cases blow up intake manifolds. When the DME requests a torque drop due to traction or stability control the JB4, WMI, and PI systems all respond accordingly. JB4 anti-lag has a dedicated user adjustable boost limiter to avoid unnecessary engine stress while engaged. WMI integration is able to hold boost levels low UNTIL fluid is flowing adequately to prevent spool up and transitional knock, adjust your boost target if the fluid being injected turns out not to be as potent as was expected or required to prevent knock, and in the event of a fail-safe depending on the severity of the situation either lower your boost target partially OR instantly dump boost out the diverters/close the throttle/cut timing. These are just some of the many examples of why having add on boxes an features all integrated through a single system is advantageous.

6) The JB4 is widely used and widely supported including free unlocked back end flash maps and custom mapping support from BMS via the n54tech support forum. BMS sponsors and attends several 1/4 mile and 1/2 mile races per year continuously improving the JB4 base maps and features based on real world experience and feedback. These updates are provided free of charge to JB4 customers via n54tech firmware posts.

7) The JB4 hardware is robust, reliable, highly developed, and upgradable, with many thousands of systems in use since 2008 when it was first released. The key to the JB4’s success is that it DOES NOT replace the factory engine computer or DME. The JB4 simply adds on to functionality already provided by the DME. As a result the DME remains in full control of your engine at all times with the JB4 dynamically making small but impactful adjustments to add in extra safety systems and features and dramatically improve performance.

Use Guide:

To load the flash first set the JB4 to map0 disabling it's CANbus. After loading remove the android device, select mode 4/2 in dash so your JB4 knows you're running a BEF, and then select your normal JB4 map. No other JB4 settings needed. NEVER select 3.5bar TMAP in MHD when flashing even if equipped with a 3.5bar TMAP sensor as the JB4 is already programmed to do that conversion.

PUMP: Suggested for most applications ranging from 91/93 octane up to E85 mixtures of around 40%.
E85: Suggested for E85 mixtures of 40% or more.
E85_PI: Suggested for E85 mixtures of 50% or more with the use of methanol injection or port injection.
E85_PI_ST: Same as above but optimized for larger single turbo use.
THR: Factory throttle mapping, some cars running xHP trans software have reported smoother performance with factory throttle maps.

Templates are provided for reference only

8/17/17 JB4 MHD N55 Map Release

1) Added 9E60B back end flash maps for use with 2012+ models that have undergone the MHD unlock procedure. 2011-early 2012 models flashing via MHD will continue to use 98G0B files.

7/14/17 JB4 MHD N55 Map Release

1) Corrected torque scaling that was inadvertently removed last version

2/23/17 JB4 MHD N55 Map Release

1) Adjusted load to eliminate a potential misfire problem on higher boost cars
2) Combined USA and EU files so EU vehicles no longer need a dedicated file

The TunerPro XDF definition files are available at Download everything as .zip. TunerPro is free software:

Burger Motorsports
Home of the Worlds fastest N20s, N54s, N55s, S55s, N63s, and S63s!

It is the sole responsibility of the purchaser and installer of any BMS part to employ the correct installation techniques required to ensure the proper operation of BMS parts, and BMS disclaims any and all liability for any part failure due to improper installation or use. It is the sole responsibility of the customer to verify that the use of their vehicle and items purchased comply with federal, state and local regulations. BMS claims no legal federal, state or local certification concerning pollution controlled motor vehicles or mandated emissions requirements. BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways. Please click here for more information on legal requirements related to use of BMS parts.
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