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Terry @ BMS Terry @ BMS is offline
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Default F Chassis N55 MHD Back End Flash Maps - 10-02-2017, 12:33 PM

With the recent release of F series OBDII flashing tools for MHD its time for a central thread for development discussion, FAQ, JB4 BEF map distribution, etc.

Suggested Flashing Cable:

S55 M3/M4 BEF Maps are posted in their own thread now:

General directions:

1) Download MHD F Series Flashing software to your android device.
2) There is a ~$200 per VIN license fee for flashing maps. You will not need to purchase any map packs as BMS is providing those free of charge, and you also do not need to purchase a logging module as you'll be using the JB4 for logging.
3) To flash just unplug the JB4 from the OBDII port while flashing and plug it back in when done. You don't need to set the JB4 to map0 before flashing because with its OBDII removed it can't interfere on the CANbus
4) Flash "Stage 0" using the MHD tools to start. The initial flash takes around 20-30min so a battery charger is suggested. Assuming it loads properly and the car starts, you're good to go.
5) Load the latest JB4 firmware for your vehicle. We've recently redesigned all F series firmware for must faster datalogging and added extra channels to facilitate dialing in the back end flash maps.
6) Set FutureUseD #6 on. This is going to become the universal F series flag to let the JB4 know you've equipped the vehicle with a back end flash map triggering whatever tuning changes we want to happen on the JB4 end as a result.
7) After successfully flashing "Stage 0" download and load the appropriate BEF from the package at the bottom of this post. You will load the BEF using the "Flash a Backend" option within MHD which ports the changes we've made over to your specific ECU when flashing.

Note once installed and the JB4 is set to BEF mode (FutureUseD bit6 on) the boost targets on each map will change to higher boost absolute maps designed specifically for use with BEF maps. Actual boost targets will vary by JB4 firmware version.

As always our JB4 BEF maps will be provided free of charge and fully unlocked so those of you who are interested can tweak them to your specific needs.

Click here to download the latest 8/2/18 maps. Note they are subject to change and when we make revisions we increment the number on each one to keep track of the changes.

Recent changes:

1) Addressed false alarm under boost fault code in various map versions
2) Minor changes we've made along the way during development
3) Incremented the version of maps within the same family to avoid confusion

There are several F series models that each require a unique map. To differentiate them we've labeled each file:

EWG: 2014+ EWG models (except M2 and S55 models)
S55: 2015+ M3/M4 models
PWG1: For the PWG models I'm not sure yet which cars need which one, but MHD won't let you load the wrong one. Most cars seem to be PWG2.
M2: They have their own dedicated map set

PUMP: Intended for low grade fuels.
RACE: Intended for use on pump fuels and E85 mixtures up to 50%.
E85: Intended for use on heavy E85 mixtures of 30-100%. Note the N55 generally has a hard time supporting more than 30-40% E85 due to a weak high pressure fuel pump. If your fuel pressure is crashing you know you need to reduce the E85 mixture, reduce boost, or add in WMI or port injection.

Starting work on the FAQ. It's a work in progress. I'll update it as I see more questions come in and as development progresses.


What benefits does a back end flash map add to the JB4?

Adding in the back end flash map allows JB4 adjustment over a wider range of engine parameters than are available on the factory flash. Including direct adjustment of timing and fueling tables, VANOS adjustment, fuel scalar adjustment for heavier E85 mixtures than possible JB4 only, speed limiter delete, optional exhaust burble, higher calculated torque reported to the automatic transmission, and a host of other parameters than are only possible via flashing the DME.

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

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

1) With JB4s unique features and logic paths, combined with the flexibility of adjusting DME tables directly via the back end flash map, you get better quality, safety, and more powerful tuning. 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, and the only fuel pressure safety provided is when fuel pressure drops down so low fuel injection itself has to be suspended.

2) More mapping options including absolute boost target maps. The JB4 boost control system is programmed to offer both absolute and additive maps. 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 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, exhaust flap position, 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. You're able to make the changes while out on the track where you need to make them.

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.

5) Integrated JB4 features such as anti-lag, 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. When the DME requests a torque drop due to traction or stability control the JB4, WMI, and PI systems all respond accordingly. 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 diverter/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) Does not require a MAP sensor change for higher boost levels. On S55 models the JB4 can control up to 36psi with both factory sensors, and on N55 models can control up to 21psi with both factory sensors, and 36psi by replacing the TMAP sensor only with a 3.5bar. In addition to saving money on a 3.5bar MAP sensor on the S55 in particular it reduces headaches having to switch the hard to reach MAP sensor back to stock when flashing to stock.

7) Free maps for life. 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.

8) 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. And unlike disposable flash maps the JB4 is a physical system you can remove and resell down the road.

Once I flash the DME can the dealership tell? What if I flash it back to stock?

Modifying your vehicle is not without risks and we believe flashing the DME is traceable even if flashed to stock. If you are really concerned about your warranty, it's best not to flash your vehicle. That said when used in conjunction with the JB4's expanded safety systems and mapping use/guidelines, expect a relatively high level of reliability at the elevated power levels.

What flash time options are available?

Certain settings can be toggled on/off or adjusted during the flashing process itself. Including the user adjustable exhaust burble settings, speed limiter delete, cold start delete, CEL delete, etc. MHD will be adding these as their development progresses.
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