RB30ET, 300ZX, 280ZX injectors

[Hal]

Information I've dug up so far indicates that the 81 - 83 280ZX and the 84 - 85 300ZX used the same injectors?
Were they the same JECS 1Z42 or 2Z42 injector as used in the RB30ET?

[Matt]

RB30ET are 270CC injectors. I think they may be similar but not sure on part numbers

All the info I got so far between models is
http://www.redz31.net/pages/fuel.html

[Hal]

Cheers Matt, the reason I ask this is because the Intermotor FJ23 injector is being sold on ebay as a replacement for the RB30ET injector, but Intermotor have told me that the FJ23 application is for 81 - 83 280ZX and 84 - 85 300ZX.

I have found that the FJ23's must have slightly more latency than the 1Z42 jecs and run lean [misfire] during warm-up while the ecu is running in simultaneous injection mode [engine temp < 50c] The pulse width gets very narrow at just below the switch point.
As soon as the ecu switches to group, the FJ23's run fine.
I put the jecs back in and they run perfect at all temps.

[Hal]

Here are some cro trace pics of the injection pulse at various temps [shown as sensor resistance]
This first one is just after start-up at about 15c.



This one is after a few mins of idling. The engine is struggling just a tad.



This one is close to the sim/group switch point of 50c



And this one is immediately after the switch point, now in group mode and much wider pulse again.





Here's a 30 sec vid of the change in exhaust note at the switch point.
This vid was shot after having changed out one injector in the original batch of six, that could not deal with the narrow pulse width at all and would end up in hard misfire until the ecu switched to group.
https://www.youtube.com/watch?v=A2z7K4mmPYM