Haltech E6M - Manual (Page 116)

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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.
The Home trigger is wired to the same input as the Road Speed. This means that the Road
Speed input, and consequently the Torque Converter Output, cannot be used with Direct Fire.
B.2.3 Coil Set-up
To give an example of how to match the coils to the ignition outputs, we will use an example
of a V8 with an arbitrary firing order: 1, 2, 7, 8 - 4, 5, 6, 3. The companion cylinders are the
corresponding cylinders in each half. Therefore the companion pairs and their coil numbers
would be: Coil One, cylinders 1 and 4; Coil Two, cylinders 2 and 5; Coil Three, 7 and 6; Coil
Four, 8 and 3. The coil numbers then match up with the ignition Channel numbers. The
diagram below shows how the coils would be connected.
Figure B1. Coil layout for V8 with firing order 1, 2, 7, 8, 4, 5, 6, 3.
It is not necessary for coil one to connect to cylinder one. If, for instance, the original Home
trigger occurs before cylinder 6 (not common, but possible) then coil one would need to
connect to cylinder 6. The coil order would still be the same.