Haltech E8 - Manual (Page 76)

Haltech E11/E8 Instruction Manual
Tuning Guide
Introduction
Before you begin this section of the manual, make sure that you are able to start your engine and achieve
a steady idle. This section of the manual will guide you through the tuning of your fuel, ignition and
correction maps for your vehicle. The Halwin software controls for tuning maps will be covered in this
section in detail.
This Tuning Guide assumes basic knowledge of automotive fuel, ignition and triggering systems. If you
find settings or concepts that are confusing or difficult to understand, please refer to the appendices of this
manual for more background information on these topics.
What are maps?
The injection times needed by the engine at different conditions are stored by the ECU in a table of
numbers called a look-up table. The ECU determines the engine's load and speed, and uses these two
parameters as an index to the table. This table is called the Fuel Map. 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.
The ECU then holds the injectors open for that time on the next injection.
The Ignition Maps work in a similar way, except that it is the ignition advance that is stored in the look-up
table instead of the injection time.
Mapping an Engine
Mapping the engine involves filling the look-up tables with the correct values for your engine. Adjusting the
heights of the bars within the maps does this. 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
Using Halwin for Tuning
When referring to mappable points along the load axis, the convention is to refer to them as load ‘Bars’.
The convention for referring to mappable points along the RPM axis is to use the term RPM ‘Ranges’.
Halwin 3D Maps
The 3D maps form the basis of the engine tuning process. From the basic 3D Fuel and Ignition maps, the
ECU accesses the base fuel and ignition timing requirements for the engine for a give load and RPM. The
E11 ECU allows for two base fuel maps, and two base ignition maps.
Figure 79
3D Graphic Mode
To access the 3D maps, select Maps from the menu bar until the menu opens and drops down another
selection of options. From these options, select one of the Fuel Delivery or Ignition maps. Clicking on one
of these maps will reveal a second panel that will allow you to select the 3D view for the selected map.
Page: 76 Copyright © Haltech 2008
Injection
Time
(Height)
Load
(Bars)
RPM
(Ranges)