Map Editor, Tuning Suggestions, Map Configuration and Feature Activation Options - CustomROM V2
Map Editor, Tuning Suggestions
In this CustomROM V2 update you’ll see a number of tables where Intake Manifold Pressure (MAP) or Manifold Pressure Target (MAP Target) are used for axis which have equivalents in both Metric and Imperial Units. DME always uses Metric Absolute pressure values everywhere and we stuck with that approach with any of the new CustomROM V2 tables. However, as its easier to work in Imperial units (e.g. PSI) we added equivalents in Imperial for any table that uses the above as axis.
There’s no need to update both hPa (Metric) and PSI (Imperial) versions of the same table. They point at the same calibration area in the DME. We suggest edit/commit/import are only done to one of them when tuning as there’s no need to edit both and in fact it may create confusion for the tuner.
As an example we’ll show you Secondary Port Fuel Injector Calibration in both Metric and Imperial for the Fuel Pressure Differential axis below:
When we do the tuning here, we always use the Imperial (PSI) version of the table, but choice is yours.
All CustomROM tables V1 and V2 use absolute units for pressure. E.g. Manifold Pressure (MAP) or Boost (MAP) Target use absolute units that do not include ambient pressure just like the rest of the DME works with any pressure sensor.
Pressure sensors used with CustomROM V2 should always be absolute sensors that include ambient pressure in their values, not sealed gauge type sensors that only measure pressure above atmospheric.
Example: Honeywell 100psi pressure sensor part number MIPAN2XX100PAAAX is an absolute pressure sensor and is the one to be used for instance for Manifold Pressure (MAP) so it can be appropriately calibrated in the DME. You should not use the Honeywell MIPAN2XX100PSAAX sealed gauge sensor as it won’t be possible to calibrate to exact specs.
CustomROM V2 introduces a number of activation switches for various features under BM3 CustomROM → Configuration as shown in below screenshot:
Active Maps (MapSwitch)
This table indicates how many map slots will be active in this particular map. For a value of 4, it indicates 4 map slots are configured in this map and made active for map switching on the steering wheel.
Boost Ceiling By Gear Switch
Original DME logic uses a 1D Boost Ceiling table that doesn’t lend itself to tuning boost by gear in a convenient way. We’ve added a customization that provides a 3D Boost Ceiling By Gear (Gear vs RPM vs Boost Ceiling) table to each of the map slots, Flex Fuel, as well as AntiLag (6 tables in total). Setting this table to 1 enables use of the Boost Ceiling By Gear tables so ensure that they’re set appropriate for your boost target. Here’s an example of this new table under Map Slot 1 with a progressive boost target (ceiling) set using Gear vs Engine RPM:
Boost Ceiling By Gear is available in the Map Editor under the following:
Map Slot 1 - 4 Boost Target folder
Flex Fuel Boost Target Folder
AntiLag Boost Target Folder
Click here for further details on Boost Control with CustomROM V2.
Map Based Activation (AntiLag)
This table is carried over from V1 and provides for a way to set which of the 4 map slots has AntiLag enabled. Setting a 0 will disable AntiLag in that map slot.
Map Based Activation (FlexFuel)
This table is carried over from V1 and provides for a way to set which of the 4 map slots has FlexFuel functionality enabled. Setting a 0 will disable FlexFuel in that map slot and Flex Fuel tables will not be blended. If disabling FlexFuel on a map slot to run a fixed ethanol concentration fuel see Flex Fuel section of this wiki.
Stoichiometric Ratio (Dynamic) Activation
FlexFuel handling has been done differently in V2 and is much more advanced now. Ethanol content is now fed into the fuel mass equation and stoichiometry of the fuel can be dynamically adjusted on the fly.
In V1 the fuel scalar table adjustment was used as a blend table to adjust the DI fuel injector flow and compensate for the additional fuel required for ethanol based on Ethanol %.
In V2, you simply activate this feature, leave the fuel scalar tables at OEM values (close to 1.0) and the fuel mass equation in the DME does the rest.
For those without a flex fuel kit or REV2 Board installed, we added Stoichiometric Ratio 1D tables per map slot so you can leave this activation at 0 and use those to set the stoichiometric value of your fuel in a static way while still taking advantage of this great feature and the automatic nature of the fuel mass calculation without a need for any DI fuel injector scaling.
TCU Torque Limit Bypass
In CustomROM V1 we had a toggle in map config to optionally remove any DME torque intervention that is based on TCU control messages.
Some RWD customers requested an additional option to maintain the control messages between the TCU ↔︎ DME only during launch control, and otherwise to turn it off as before. That option is now available through map config, and through the above table in Map Editor for any custom maps, with the following options:
Ethanol Content Analyzer Configuration (Ethanol Hold)
In CustomROM V2 when using the REV2 Board, ethanol content analyzer function has been moved inside the DME and we’ve introduced a new function called Ethanol Hold.
For vehicles under WOT, high load, there are situations where fuel pressure going through the ethanol sensor can cause some deviation from the true ethanol % reading. Without our Ethanol Hold feature, DME fuel mass calculation can be slightly impacted in a slightly incorrect way (e.g. 88% ethanol being reported as 82%) due to this mechanical nature of the ethanol sensor. While in most cases this won’t cause any issues, we’ve decided to add the Ethanol Hold feature which provides for holding the ethanol % reading constant while under WOT/high load situations and re-enabling those readings after the value set for Reactivation delay in above tables. Minimum Pedal, Boost Pressure and Engine Speed are minimum thresholds that need to be met for Ethanol Hold feature to go active.
We also noticed that during engine startup, ethanol readings can deviate in a large way as fuel passes through the ethanol sensor. Average Ethanol Hold (Activation) is a switch that will allow for smoothing those values using the provided Buffer Sample Delay, Buffer Sample Size and Clear Ethanol Hold Buffer Sample (Activation) tables. We’ve also added ability to store last seen ethanol reading in DME’s NVRAM for the pre-configuration duration to further assist engine startup in these situations.
Recommendation is to leave the default settings in place on any new custom tune requests and only adjust if/when necessary.