Discussion and questions related to the course Practical Harness Construction - Club Level
Good evening team.
I am in the process of building an engine loom for evo 5.
I am converting to a cop setup and im using a g4 plug in ecu.
I know from factory they only ever used 2 coils firing cylinders 1&4 and 2&3 respectively.
I know there ign 1&2 on the g4 pinout is allocated to the coils.
My question is, is it better just to wire the cop setup signal wires just like factory or is it better to wire all 4 coils to seperate ign outputs.
Wiring them to seperate ign outputs makes sense to me but need confirmation of my theory.
Thanks in advance.
Yes wire them individually.
What you have provided is called "Wasted Spark” ignition system. If you have spare 4 ignition coils that will fit to your engine than you can run “COP” ignition system. Otherwise “Wasted spark” would do the same job except each coil will fire twice per engine cycle.
On a 4 Cyl with the current G4+ system, the main advantage with changing to direct spark is it means you can then you can do individual cylinder ignition trims (including individual cylinder knock control). In wasted spark mode the cylinders can only be ignition trimmed in the wired pairs.
Since a very small minority of the many ecu files I see daily are set up with individual cylinder trims or knock control I would say this isnt a big deal for most users and you are not going to see any other performance gain from direct spark vs wasted (until you get over about 10000RPM).
As I know in a Wasted spark mode you still can use Individual cylinder ignition trims.
No. Info from help file below.
thank you very much for that adam.
I guess the reason i want to do it this way is because ive gone to a COP ignition coil.
the other reason is that i have changed the original radiator fan which had 2 different speeds to an aftermarket fan that doesnt have that capability so it using the RAD FAN HI Ign 4 (pin 20) output for the coil seemed sensible.
I am planning on running the fan off the RAD LO output (pin 21) since it will only be able to run at 1 speed anyway.
I guess i could look at using PWM for the rad fan as it runs off AUX 1 anyway.
Do you see any issues with this?
I am really just trying to make the most out of the I/O of a plug in ecu.
I will also mention i have a G4 ecu and not the g4+.
Yes, it will work fine. Make sure you also have nothing connected to pin 32 & 34 (these are also connected to Ign 4 on that plug-in).
thanks heaps for that adam.
and obviously i can do the same with IGN 3 as that just runs the AC compressor and the car has no ac?