Nissan FJ20 Turbo Injection System

[Steve Lamb]

>I have a question regarding a 2 litre Alfa Romeo turbo efi engine which
>I am building. The engine will utilise an Autronic SM2 computer (I'm in
>Australia btw), DFI (from a Subaru WRX) and injectors from a Nissan FJ20
>turbo. I need to know the following:
>1./ Do I need to use ballast resistors in-line to the FJ20T injectors,
>or can the Autronic SM2 software dispense with the need for this?

With a standard FJ20(T) system ballast resistors are normally used.
Measure the injector resistance - if its about 2.5 Ohm then resistors would
have been used.  But if the Autronic system is anything like a Motec (and
supposedly it is) then you should be able to dispense with the resistors.
Suggest you ring Autronic to be sure, they're not far up the road from
where I live in Melbourne.  If you need their number let me know.

>2./ What is the max flow rate of the FJ20 Turbo injectors and their max
>hp capacity (each)?

I'm told NA FJ20 injectors are good for about 50HP each, so the FJ20T
versions should be OK for around 70+ (??), but I'm yet to find any 'hard'
data.

>3./ I have seen 3 different injectors for the FJ20T all stamped A46-00
>on the side but with 3 different numbers stamped on the top: 4144 2525B,
>41443205B or 4144 3309B. The colour of the plastic moulding differs
>between each of the three injectors also, but is there any performance
>difference and can they be interchanged and mixed in the same engine?

I would be a bit concerned about the different colouring/numbering of the
injectors.  All the sets I've seen from Nissan engines have been the 'same'
- are you sure all the injectors were taken from the same engine ?? (if
they were you should be OK).  'Mixing' injectors is not a good idea unless
your absolutely sure that all the injectors came from the same engine type
- and preferably from the same model series.

>4./ Anyone got a wiring diagram for the Subaru WRX direct fire ignition
>system?

Some of the Motec documentation I have may have something about this - I'll
check on the weekend.  But, again, Autronic should be able to help here.

Cheers


Steve Lamb
Department of Defence, DSTO
Aeronautical and Maritime Research Laboratory
506 Lorimer Street
Fishermans Bend  VIC 3207 Australia

Tel: +61 3 9626 7525
Fax: +61 3 9626 7089

IZCC #180