VW AG EA888 RaceROM Custom Map Example's

Owned by Lucan Hetherington
Last updated: Nov 08, 2022
7 min read

Contents

Introduction

As part of the V3 RaceROM update custom maps have been added to the Simos 18.X ECU’s this allows the tuner to make features using the available inputs and outputs. The custom maps feature guide is (https://ecutek.atlassian.net/wiki/spaces/SUPPORT/pages/13598721) for notes on general setup, logging and usage. This article is intended to highlight some possible features that could be generated using Custom maps.

While hardcoded features would be ideal to speed up tuning due to the available space in the SIMOS 18.X ROM architecture having all of the features that might be require included on all of the ROMs is problematic. Hence the use of custom maps to allow you to set up many different types of features depending on your customers desires.

Some features that are setup in custom maps on other platforms and can now be done on the EA888 are

  • Rolling Launch

  • Adjustable Launch Control

  • Adjustable Traction Control

  • Push to pass

  • Nitrous Control (using CAN Outputs and external hardware)

  • Methanol Injection (using CAN Outputs and external hardware)

In this article we will show some examples of how to set up custom maps to create features that can help with performance.

Rolling Launch

Rolling Launch is a useful feature that can be used in cars for Roll Racing and can be used in conjunction with Brake boost etc that can be set up using the OEM maps. For a rolling launch function in Custom maps you may want to do the following

  • Only have the function active when the Cruise “Set” button is pressed.

Map 1

Apply an ignition retard to reduce the actual torque delivered when Rolling and to attempt to create enough exhaust energy to actually spool the turbo. this map can be set up to be a base ignition retard amount based on RPM and boost target.

Map 2

Apply a Boost target minimum to force to pre throttle boost target to a value that we want. This will lift the actual torque produced even with the ignition retard so we may need to control the torque still (the last degree of freedom left is the throttle so the ECM can close this to reduce torque)

Map 3

Apply a Torque limit to stop the car from pulling away too hard. the torque limit will also limit the boost target so fine tuning will be necessary

If brake boosting is to be used while Rolling Launch is active the OEM maps will need to be set up to allow this.

The three maps don’t need to have large resolution so we decided to use the smaller 12 x 8 RR maps from Custom Map M to O, this means that

  • Custom Map M = Ignition Retard Map (you will need to adjust OEM minimum timing maps as well)

  • Custom Map N = Boost Target Adjustment

  • Custom Map O = Torque limit (to stop creep)

The run down on how to set up the maps is as follows

Map 1 (Custom Map M)

To set this up in Custom maps we first need to enable the Map in the desired Map switch modes and active only when the cruise “Set” button is pressed. In this case we use Custom map M Enable due to its 12 x 8 size and set the activation for map switch mode 4.

The next step is to set the axis values up for Custom map M, as previously discussed engine speed and boost target will allow us to target more ignition retard when if the boost target is higher.

the axis Values also need to be put into the map

The next step is to set the output of the custom map up, in this case we want it to reduce the ignition timing value, you could also add or replace the value but for simplicities sake we have used the “Use output as Maximum for Channel Value” so that we don’t effect the normal ignition timing values when we are not in the rolling launch rev range.

Finally You can Populate the map with values, these values will need to be tuned for your specific car. We have gone with a base setpoint of -10deg at high airflow amounts and medium RPM band.

More advanced users may want to add a proportion correction on here using an add map value to calculation channel based on boost error to prevent any sort of bogging that may occur when you reduce the ignition timing.

Map 2 (Custom Map N)

Map 2 is designed to request a boost target that is what we desire so we can increase the pre throttle boost ready for the rolling launch, usefully in the SIMOS18.X ECU’s when you apply an ignition retard it will try to target a high enough manifold pressure to maintain the requested torque value. It was found in testing that the boost target was not high enough when applying just a retard so we will lift it artificially with this map.

this map uses the same enable and axis set up as the map above (for ignition retard) so you can copy and paste the values from this map (using CTRL + ALT + C to copy and + V to paste)

Enable Setup

Enable map in Mode 4, Enable when CRUISE SET held

Axis setup

X input Accel Pedal, Y input Engine Speed

Output Setup

Output channel: Boost Target (hpa)
Output function: Use map output as a minimum for channel value

Map Values

we set this to not raise the boost target when we are outside of the airflow and RPM bands, so if you are not in the right region rolling Launch doesn’t get in the way.

Map 3 (Custom Map O)

Map 3 is designed to limit the torque so that the boost target does not get too high and you can can slowly accelerate if required by using more accel pedal when RL is active. We have used the next map in the list custom map J for this and have set up the Enable parameters, X axis, Y axis and Output as follows

Enable Setup

Enable map in Mode 4, Enable when CRUISE SET held

Axis setup

X input Accel Pedal, Y input Engine Speed

Output Setup

Output channel: Torque Demand Pedal (Nm)
Output function: Use map output as a maximum for channel value

Map Values

Finally we populated the custom map itself with the desired limit values, in this first step we have selected a limit of 150Nm up to 200 NM at full Accel Pedal. this will need to be tuned for your specific vehicle setup.

this can then be tested on the car to see how it goes, in our dev car we saw these results with the maps operating. As you can see in the logs that the maps are applied to the engine operating states and you can feel the response.

Attached is a Diff file with the settings applied, this also has the minimum ignition settings included for reference. NOTE: Check your OEM Ignition Timing minimum maps for suitability before using this in a car.

Some other examples that can be set up in custom maps are

  • Rolling Launch

  • Adjustable Launch Control

  • Adjustable Traction Control

  • Push to pass

  • Nitrous Control (using CAN Outputs and external hardware)

  • Methanol Injection (using CAN Outputs and external hardware)

Here are some more diff files to use as a base to set up particular features

Maxx ECU PWM CAN output

This diff file contains the CAN and custom map settings to

 

Adjustable Launch Control for Manual car (test on Seat Ibiza 1.8)

This diff file contains the CAN and custom map settings to

  • Custom map A - Launch Control enable (vehicle speed accel pedal and Clutch Switch)

  • Custom Map B - Launch Control Boost Target minimum setpoint (RaceROM Controller Input)

  • Custom Map C - Launch Control Ignition Setpoint for Boost off the line (RaceROM Controller Input)

  • Custom Map D - LC fuel cut setpoint (multiplies Fuel Quantity) (RaceROM Controller Input)

  • Custom Map E - LC torque limit (FWD cars & traction hey.) (RaceROM Controller & Rear Wheel speed as Input)

NOTE: these settings contain a fuel cut and large ignition retard, please use with Caution and test with low targets to see the strategy works.

For more examples please contact support@ecutek.com.