Haltech E6M - Manual (Page 149)

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G.M. Direct Fire Ignition
The G.M. Direct Fire Ignition module (DFI), as used in the V6 Buick, can be connected
directly to the E6H/E6M ECU. This module serves both as a trigger device and as an igniter.
For a wiring diagram, see Appendix G. The DFI module has an ignition bypass input from the
ECU. This input tells the DFI module to ignore the ECU’s timing signal and fire its own spark
at 10° BTDC. This gives a more reliably timed spark for cranking. This input is controlled by
the E6H/E6M through the Aux. Out Function. To use the bypass, this function should be set
in the Identification to Bypass. Refer to 13.1 The Input/Output Page. The bypass will allow
the DFI module to control spark below 450 rpm
Ford Thick Film Ignition (TFI)
The Ford TFI module is fitted to distributors used with Ford’s EEC IV engine management
computer system. The E6H/E6M ECU can connect directly to this module, however, the TFI
module requires a trigger signal, call the SPOUT (see below), that has a 50/50 duty cycle,
which is not the standard 70/30 duty cycle of the E6H/E6M. To use the Ford TFI module you
will have to adjust the Ignition Output Duty Cycle in the Ignition Set-up (see Chapter 4 on
Accessing the Ignition Map) to 50.
Signal Names for TFI Module
PIP Profile Ignition Pickup Output
(trigger pulses from the Hall Effect Sensor)
SPOUT Spark Out (Igniter output from the ECU) Input
POWER + 12 volts from starter circuit Input
POWER + 12 volts from ignition switch Input
COIL - Negative terminal of coil Output
GND Ignition system ground
There are several versions of the Ford TFI module but these notes only refer to the type IV
module. This TFI module is physically attached to the side of the distributor and connects
directly to the HALL Effect pickup within the distributor.
To further complicate matters there are two types of chopper wheels used inside the
distributor, one that generates a normal’ PIP signal and one that generates a ‘signature’ PIP
signal. With the signature PIP, the pulse for cylinder one is shorter than the pulses for the
remaining cylinders. This is similar to Figure E.3 except that the cylinder one pulse is shorter
rather than longer. Unfortunately the edges where the pulses do coincide occur at 10° BTDC.
Therefore the E6H/E6M cannot be used with a signature PIP unless the trigger point is
moved. If the trigger is modified be wary of rotor phasing (See Appendix F). The trigger edge
for the Ford TFI module is falling edge. For 8 cylinder engines the Trigger Angle is 55° and
for 6 cylinder engines it is 70° BTDC.