Nistune Forums

Hi!
I lost track on what you want to swap but from Z32 to RB25 nothing has to be swapped because the loom 'sorts it out'

(The loom actually connects the injectors/firing in the correct order)

foliage wrote:Just want to be 100% that it is sequential as those posts make it sound like it may not be, also if it is sequential if pins need to be swapped between two injectors. Matt later said it wasn't necessary? Do you know why he said this?

Haha you are awesome pete, thanks for looking into it!

If the pins do need to be swapped would explain the idle misfire me and another member have. I just put it down to running lean at idle.

Mainly interested in the rb20 ecu as that is what I am using with my rb25det.

i've always been under the impression the rb20 ecu's were in batch mode. i've seen some ecu's fry an injector driver and 3 injectors die at once.

i've also never noticed ANY ill effect from running an rb25 on an RB20 or Z32 ecu without any wiring change.

Here's my 2 cents worth.

Z32 ECU's run batch/sequential injection, that's why it's important to re-wire after a Z32 -> R33 conversion as the fuel in injected at a particular crank position with respect to RPM.

SR S15's run batch/sequential injection, as I've just spent the afternoon repairing a blown-out injector driver
SR S14's run batch/sequential injection
SR S13's ran batch mode, but are should to have sequential available under correct conditions
RB26's run batch/sequential injection
RB20's run batch/simultaneous injection (front & rear 3 cyls)
RB30's run batch and simultaneous injection (Front/Rear 3 cyls) (with an rather smart driver cct!!)

Nissan's terms are a little different from some other EFI systems.
Sequential means starts at cyl 1 and follows firing order, with a programmed & defined 'end of injection point'
Batch (or group) means the injection is broken up into 'Banks'. Each bank alternates every 360' crank rotation
Simultaneous means ALL injectors fire at the same time, usually twice per eng rotation - often used for starting or limp home mode

Remember that there are many 'hard coded' conditional modifiers that allow the system to change in and out different modes based on temperatures, road speed or any other variable the embeded software engineers choose to implement.

Interesting information stu, is that all from first hand experience?

That would make my days since I always thought Z32 is sequential/batch.

(I think batch is used at higher loads)

Pretty much - i do 'off label ' mods to many varied ecu's, so I have a simulator/comverter that I feed logged data thru and into the efi hardware direct, effectivly 'running' the ecu in the car. Then I monitor/hack anything i like with heaps of other trick gear i have in the armoury.

You can trace out the pcb inside the ecu to deterimine it for sure though.

@torque : Yeah, its in the workshop manual for the Z32, sequential when running, simultaneous at cranking.

I certainly stand corrected on the RB20 (I tihnk I knew this but have bad memory!) - I traced out the tracks on an 04U01 R32 RB20 ECU on the weekend and they're certainly in 2 batches. Cyl 1,3,5 grouped and 2,4,6 grouped.

Stu, I've never seen sequential on SR20DET. No matter what conditions I simulate. Am I missing a condition under which they do run sequential?

PL

Pete do you have a neo r34 ecu lying around? Curious if that is also batch fire.

Will check tonight.

PL

I'm getting confused now

If you say they are grouped (and I presume this is in hardware) how can they be sequential??

PL wrote:I certainly stand corrected on the RB20 (I tihnk I knew this but have bad memory!) - I traced out the tracks on an 04U01 R32 RB20 ECU on the weekend and they're certainly in 2 batches. Cyl 1,3,5 grouped and 2,4,6 grouped.

Stu, I've never seen sequential on SR20DET. No matter what conditions I simulate. Am I missing a condition under which they do run sequential?

PL

Torque wrote:I'm getting confused now

If you say they are grouped (and I presume this is in hardware) how can they be sequential??

It isn't sequential, he corrected himself.

Sorry .. I seem to be missing that correction message?!
Who corrected what?

foliage wrote:

Torque wrote:I'm getting confused now

If you say they are grouped (and I presume this is in hardware) how can they be sequential??

It isn't sequential, he corrected himself.

Torque wrote:Sorry .. I seem to be missing that correction message?!
Who corrected what?

foliage wrote:

Torque wrote:I'm getting confused now

If you say they are grouped (and I presume this is in hardware) how can they be sequential??

It isn't sequential, he corrected himself.

PL traced the tracks, the ECU fires in batch fire, eg 3 injectors at once, not sequential.

The pins for injectors 1,3,5 are shorted together at the ECU connector for R32 RB20DET 04U01. Same for 2,4,6.

I'd call this "grouped".

This is sooo much fun!

PL