Haltech E6A - Manual (Page 99)

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With either method, the importance of the setup to the E6A is the number of coils. Each coil
needs its own igniter and ignition output. On a four cylinder using waste spark, two coils are
used, and, therefore, two ignition outputs are needed. In this case, channel 4 is used as the
second ignition channel, making it unavailable for auxiliary outputs. The six cylinder with
waste spark is similar. It requires 3 coils and 3 ignition channels. For this setup, channels 4 and
5 become ignition channels 2 and 3 respectively, and neither is available for Auxiliary Outputs.
A V8 becomes a little difficult. It requires 4 coils and 4 ignition outputs, but we have no more
available outputs. Therefore, we take one of the fuel drivers and use it as an ignition channel.
The E6A uses channel 1 (marked on the loom as) for this purpose. This channel becomes
ignition channel 4. There is some trade offs with this though. Multipoint is the only available
injection mode. The batch fire and staged modes are not available. Also, because there are only
two injector drivers left of controlling fuel, an Extra Driver Box (or possibly 2) will be needed
to provide enough power for all the injectors.
Using the same configuration also gives us another possibility. Since there are four ignition
outputs it is possible to use them to control 4 coils on a 4 cylinder. This option is selectable
through the Ignition Setup.
There are some other cylinder configurations to consider. 1, 2 and 3 cylinder engines need 1, 2
and 3 ignition outputs respectively. Alternatively, a two cylinder can use one ignition output
and use a direct fire coil with a waste spark. The Direct Fire Option should not be chosen. This
can only be done if the engine is not odd fire. Five cylinder engines can not run Direct Fire as
they can not use waste spark and therefore need 5 ignition outputs. Also, there are not enough
outputs to run Direct Fire on 10 and 12 cylinder engines.
B.2.2 Synchronising
On a distributed engine the E6A does not need to know the engine position. It is told to
generate a spark which the distributor sends to the correct spark plug. With Direct Fire, the
E6A needs to know engine position so that it knows what coil to trigger next. To do this, the
ECU needs to receive a Synchronisation Event (Sync. Event). One form of Sync Event is
missing teeth on a multitooth wheel. The most common Sync Event though, is a Home trigger.
This trigger needs to occur before the main trigger for cylinder (or coil) one, indicating that the
next main trigger is for cylinder one. This trigger should not occur at the same time as the main
trigger.
When the engine is started, the ECU will not generate a spark until it receives a Sync Event.
After that, the ECU fires each ignition output sequentially until it gets to the last output. It
then expects to receive another Sync Event. If it does not receive a Sync, it will not fire
another spark until it does. If the Sync is received, ECU ignition is set back to coil one and the
sequence continues.
The Home trigger must occur before the main trigger each time coil one is to be fired. For
example, on a four cylinder with waste spark, coil one needs be fired once every revolution.
With 4 coils, though, coil one fires once every two revolutions. A cam trigger would be
required for the Home.