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In a nut shell, in basic layman's terms.

The standard R32 GTR ECU is designed to have high impedance injector output.

To run low impedance injectors Nissan used the resistor pack to get around the ECU's high impedance output.

If your running a Haltech, cut and join all the 7 wires at the resistor pack and remove the resistor pack, then select VIA the ECU which injectors you want to run, high or low impedance.

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In a nut shell, in basic layman's terms.

The standard R32 GTR ECU is designed to have high impedance injector output.

To run low impedance injectors Nissan used the resistor pack to get around the ECU's high impedance output.

If your running a Haltech, cut and join all the 7 wires at the resistor pack and remove the resistor pack, then select VIA the ECU which injectors you want to run, high or low impedance.

thanks, is it true low impedance injectors have a faster reaction time over the high impedance ones or is this just horse shit lol cheers

For those wondering what the benefits are, perhaps google up "peak and hold".

It's all about how the ECU drives the injectors and how fast they open as a result.

the only useful information I found at first was pretty dated. stating that saturation-style injector design is maxed at 600cc/min.

Then I found what I was looking for here:

http://fuelinjectorclinic.com/faqs/#1

the common belief which still lingers today (though it is no longer correct) is that low-z injectors are the best for your high performance vehicle.

Today’s high impedance injectors, however, are able to outperform those older low impedance injectors at larger flow rates due to their newer designs, tighter manufacturing tolerances and much lighter moving parts. A valve and spring assembly from a current high-z injector may weigh less than 1/3rd of the assembly from an older injector.

Thanks to this newer technology the current high-z injectors are more linear throughout their pulse range; they are able to repeat shorter pulse widths consistently which means they can provide excellent part throttle and idle characteristics, and operate at higher maximum operating pressures.

I then wondered why would GTR's and GTiR's use resistor packs for low impedance injectors, when all the resistor pack does is reduce the current from the pulse?

The resistor pack is installed to ‘fool’ your ECU into thinking it is driving high impedance injectors. Vehicles that have low impedance injectors AND resistor packs have ECUs that use a saturated signal to operate low impedance injectors.

Most of the OE manufacturers that produced cars with low-Z injectors chose a “workaround” to using the low-Z injectors since it wasn’t cost effective to produce an ECU with the necessary circuitry and injector drivers to produce these P&H signals for the few high performance cars that needed it.

Did anyone even bother following my advice?

yes I did thank you it was informative although it did slightly contradict from what I have read previously about high impedance injectors being able to now run cooler as I had read they do run hotter due to the high voltage requirements. Edited by mr skidz

Proper P&H drivers would definitely throw injectors open faster than you could achieve with high impedance injectors (back in the day). Probably true that general development of injectors has left those days behind us, but it was true when they were conceived.

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