Haltech E6X Manual DOS Version - Manual (Page 105)

E6X Manual
105
B.3 Sequential Injection
Sequential injection allows fuel to be delivered to the engine at a time that produces best
combustion. Since this time is different for each cylinder, sequential systems inject fuel at
different engine angles for each cylinder. The ECU will control up to four separate fuel
channels. This provides full sequential injection for engines up to 4 cylinders, and semi-
sequential for 6 and 8 cylinders engines.
B.3.1 Injector Phasing
The timing (or phasing) of these injections is programmed through the Injector Phasing Map.
This Map sets the angle of the End of Injection, in degrees BTDC exhaust against engine
speed. This allows the injection to be completed before the inlet valve opens. If the ECU
computes that there is insufficient time to complete injection before the specified End of
Injection time, then injection will continue past this time.
B.3.2 Injector Trims
With multiple injector channels, it is possible to trim the fuel injection time to each channel.
The ECU has the ability to adjust each channel by ± 12.5%. This is meant primarily to
equalize distribution of fuel to individual cylinders due to limitations in inlet manifold design
or to ‘equalize’ flow rates between injectors with marginally different flow rates.
B.3.3 Sequential Injection Order
The ECU’s fires the injection outputs as follows:
INJ1
INJ2
INJ3
INJ4
The cycle starts after a synchronisation or home signal is detected.
The ECU can only provide 4 separate fuel outputs. For engines with more than 4 cylinders
configured for sequential injection, the ECU will operate in a semi-sequential mode.
There are 2 options for semi-sequential injection:
The first requires the user to pair the cylinders adjacent in the firing order. A 6-cylinder
engine with firing order 1-5-3-6-2-4 would have the following injector pairs:
INJ1 cyl 1 and cyl 5
INJ2 cyl 3 and cyl 6
INJ3 cyl 2 and cyl 4
This fuel scheme requires a home signal that is driven by the cam so that the ECU knows
what the engine position is in its 720° cycle. The second requires the user to pair the