V8 injector wiring

[wake77]

can anyone tell me why the wiring of the injectors is different between the vn and vr for a v8.
the vn has bothe injector outputs joined together and all injectors connected.
the vr has 1,3,5,6 on one output and 2,4,7,8 on the other.
but buy the look of the diagrams they are both linked internally.
??

[Holden202T]

well from what i've seen vn ones have D15 and D16 joined to be the injector wire whereas vr has them seperate ... may just be that it was only implemented in VR ...

i think the vr auto uses this for something ..... not sure though.

[yoda69]

I'm not sure, but was wondering if this maybe to do with firing injectors in a bank or series.
The holden firing order is 1-2-7-8-4-5-6-3 , which mean 2-7-8-4 are grouped in order an 5-6-3-1 are grouped in order.
Guess it could be used to minimise the amount of fuel hanging around if it was timed correctly, kind of a halfway step to full sequential that didn't come in until VT.
Not sure if the VR distributors had the extra sensor for cam position in them like the VT.

yoda69
Edited to fix a typo on grouping.

[Doctor Bob]

im pretty sure the two injector circuits are simply for better current handling

[hatchssv8]

yoda, you are correct in what you have said so far. They are 'grouped' injection on VR/S. It follows the ignition sequence for balance.

What I dont understand yet is how the ECM is referenced as the dizzy does not tell it where it is.

Dr Bob: you are correct also, however, if the injectors were being pulsed simultaneously, there would not be any need to group the wiring as per yoda's post.

I would like to find out the difference between the VN/p and VR/S with regards to injection management. Any ideas?

[delcowizzid]

they all fire at once

[hatchssv8]

if that is the case, why is the wiring spliced in those distict groups?

[delcowizzid]

well the order they are in doesnt make any sence anyway one would expect it to be a different order if it was firing bank mode

[hatchssv8]

the order makes good sense.
The injection isnt really 'banked' it is grouped. And the grouping is the ignition firing order 2784 - 5631. the D15 pin pulses one group and the D16 pin pulses the other. If the D15 & D16 pulsed at the same time, there would not be any need to group the injection as Holden have done. You could just do odds & evens or any combo you like.

[delcowizzid]

oh yeah i got ya now .