Haltech F10 - Manual (Page 38)

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CHAPTER 4 ADJUSTING HALTECH MAPS
This Chapter describes the fuel maps that are the heart of the F10s ability to accurately
deliver fuel to the engine.
The following instructions assume that the user has the software running ONLINE on a PC,
with the ECU powered and connected via the supplied programming cable. It is also
assumed that the user is familiar with the ECU Set-up described previously.
4.1 What are maps?
The injection times data required to fuel the engine properly at different engine load speed
temperature etc.. are stored in the F10 ECU of numbers called a look-up table. The F10
determines the engine's load and speed, and uses these two parameters as an index to the
table. This table is called the Fuel M ap. For instance, at an engine speed of 4000 rpm and at
-20kPa, the relevant number in the table may be 4.35. If the engine approximates -20kPa at
4000 rpm, then the computer will extract the value of 4.35ms from the table as the base
injection time. This value is then adjusted to compensate for numerous conditions, such as
temperature or acceleration, and then the ECU holds the injectors open for that time on the
next injection.
It is possible to program the F10 by directly changing the value of each number by
programming in the numerical mode (Refer 4.5.6 Numeric Mode, 37), but this can be
extremely difficult, so the Haltech allows you to change the numbers by manipulating
graphics in maps presented as bar graphs. (This is much simpler and allows you to visualise
the map)
Since it is difficult to interpret all the table's values at once, the programming software
divides the map by engine speed into a series of rpm ranges. Within the range, each load
point is represented by a vertical bar. When you view a range from the Fuel M ap, you see a
bar chart of injection time versus load for all the load points in the table at that speed.
There are other tables in the F10, such as those used for temperature corrections. They are
indexed by only one parameter, and so are not divided into ranges. These tables are also
called maps.
4.2 What is mapping the Engine?
M apping the engine is filling the look-up tables with the correct values for your engine. This
is done by adjusting the heights of the bars within the maps. Bars may be adjusted one at a
time, or in groups. The Haltech programming software has been designed to make engine
mapping as simple and intuitive as possible.
4.3 Using the Software
In order to make the software easy to use, the program presents you with a menus bar at the
top of the display. The menu bar is accessed through simple combinations of keystrokes.
Once the appropriate menu has been accessed a sub-menu appears giving choices on