Fuel and Timing Maps

To tune your car with the ECU+, you'll use the built-in high resolution fuel and timing maps, which give you a great deal of flexibility and accuracy for tuning.

High Resolution
The fuel maps

The fuel and timing maps are arranged in a grid for easy editing.

For a given set of fuel and timing maps, 129 cells are available. One cell is reserved for idle, while the other 128 cells are arranged as four load columns of 32 cells each. Within a load column, you can configure fuel and timing adjustments every 250 RPM, from 1000 RPM up through 8000 RPM (over 8000 RPM uses the 8000 RPM cell). In-between the RPM points, the ECU+ will linearly interpolate the correct value.

Fuel cells can be adjusted in 1% increments, from -50% to +50%. Timing cells can be adjusted in 1 degree increments, from -15 degrees (retard) to +15 degrees (advance). Both the fuel and timing adjustments are offsets from the values in your stock ECU, so zero in all of the cells give you stock performance.

The low, medium and high load points are based upon the input MAS air flow, and are fully configurable - you can select where the ECU+ switches from low to medium, and medium to high maps.

To make it easy to see what changes you've made, and whether there are large discontinuities in the maps, the ECU+ displays the maps with a New! color gradient based on the cell's value. This really makes the out-of-range values (which are usually a mistake) stand out.

Easy Editing
The editing menu

To edit a value, you just select the appropriate "cell" with the mouse or keyboard and type in a new value. You can edit the cells one at a time, or you can use the mouse along with the Ctrl key and/or the column and row headers to select almost any combination of cells quickly and easily. Once a group of cells is selected, you can use the New! pop-up menu to make global changes to all selected cells. Particularly useful is the New! Interpolate 2D menu function, which makes it easy to create a top-left to bottom-right smooth fuel map to compensate for especially large injectors.

Changes to individual cells can be (optionally) applied immediately, or as a group when the Ok or Apply buttons are pressed.

As an aide when dyno tuning, the "current" cell is always highlighted in red. This changes along with the current load and RPM of the engine.

New! Multiple Maps and Map Switching
Two built-in map sets

The ECU+ internally supports two complete sets of fuel and timing maps for your tuning pleasure. The maps are independently editable, and are colored differently in both the map editing dialog boxes and the logging screens so it's easy to keep track of what map set is being edited or is currently in effect.

The map switching configuration

By default, the primary map set is used. However, the alternate map set can be selected on the fly based on:

The five triggers listed above can be individually enabled, and map switching can be based upon whether any of the above are within range (think: condition A OR condition B OR...) or whether all are within range (condition A AND condition B AND...).

The ECU+ also includes an external +5v switch input that can be used to select which map set is used. Many applications of the switch are possible, though two simple applications spring to mind:

  1. Some external device could tell the ECU+ that it's active, and cause the ECU+ to use the alternate map set. The external device could be a nitrous, alcohol or water injection controller.
  2. The external switch could be attached to cheap Radio Shack toggle switch and mounted in-car. The alternate map set could be configured for race gas, which is then easily changed at the track. Conversely, the alternate map set could be configured so that the car ran poorly, and the in-car switch could act as a valet switch.

Saving and Loading Maps (or Whole Configurations)
Saving maps

Once you've got that perfect tune figured out, you can use the Save As button to store off your entire ECU+ configuration to a laptop disk file. At any point later, you can simply restore that "golden" configuration from disk. The ECU+ supports loading just the fuel maps, just the timing maps, just the other parameters, or any combination of these from the disk file.

The ECU+ also supports another time-saving feature - a complete system configuration is saved along with every datalog, and this includes the fuel and timing maps. So if you ever forget to save off that perfect tune, just retrieve it from a recent datalog. All the information is in there.