1680cc Injectors on FC

[RamoNZ]

I hear these need to be modded but cant find any info about - anyone done it or got any pics to describe what needs to be done?

Thanx.

[12at]

Am pretty sure its to do with the rail.. I think the injector is 14mm and the FC rail is 11mm
 
But one of the FC boys should be able to confirm - i just made up some rails for mine on my other car..
 
 
Where abouts did you get your injectors as i am in need of new ones too

[L18M]

as above, just need to mill out a bit in the rail to fit the injectors.
1680\'s can be had form clive at mrp

[RamoNZ]

So that is, rail off, 14mm drill and job done?

Cool, will give that a go

[Prof]

I think there are 2 types of 1680\'s white ones and grey ones, and one lot fit without mods I believe.

[pdtaylor18]

the ones I fitted i needed to shave about 1mm of the injector body itself,its only plastic and files down easily enough,it does not affect the sealing properties. I did it this way so i can always revert back to standard injectors for whatever reason.
The 1680 ones are low impedence injectors and will need the apexi ECU and datalogit to set them up correctly. There has been many a discussion on whether you need the aftermarket injector driver for them but it has been worked out mathematically that there is no need and you should not burn out the injector driver within the ECU.
The clips are different as well but they should come with them and you simply need to splice them into your loom.

[sadgoth]

why 1680s? I\'d fit 1000s all round as they are made to fit the FC fuel rail and you won\'t have the massive step up to the bigger injectors to worry about in the fuel mapping. Unless of course you need the extra fueling 4x1000 is 4000 (4l!) or you have 2x 550 + 2x1680 = 4460 there isn\'t much in it...

[Prof]

I think some people prefer 1680\'s as they are made as such, whereas some (not all) 1000cc injectors are bore out\'s.
 
Modern ECU\'s can control the pulse widths much more accurately, so much better fuel control with larger injectors is possible.  The old 8 bit ECU\'s just didn\'t have the resolution.

[Furb]

why 1680s? I\'d fit 1000s all round as they are made to fit the FC fuel rail and you won\'t have the massive step up to the bigger injectors to worry about in the fuel mapping. Unless of course you need the extra fueling 4x1000 is 4000 (4l!) or you have 2x 550 + 2x1680 = 4460 there isn\'t much in it...

well.. with the 1000 primairies its a b*tch to get a lean idle and cruise!
 
and if you have a decent tuner, you wont have any transition hickups
i am running 550 and 1600cc

[RamoNZ]

Where are you guys getting your 1000\'s and 1600\'s from? I need some soon

[PGiljevic]

well.. with the 1000 primairies its a b*tch to get a lean idle and cruise!
 
and if you have a decent tuner, you wont have any transition hickups
i am running 550 and 1600cc

The Apexi PFC is totally inept at running anything larger than a 850cc injector as a primary. And even that size can hardly be tuned down to give an acceptable idle.

The problem is with (not the tuner) but the physical programming of the PFC, it cant be tuned below a certain millisecond opening value, you can put in lower numbers but it wont reduce the opening time of the fuel injector (if you measure it with a scope or even look at the ms value on a datlogit for example).

Best thing is to throw the ECU in the bin! (though sadly not an option if you want to run twins sequentially).

The best injector fuel set up I recommend and use on all twin turbo cars is 4 x 850cc stock injectors with uprated fuel pressure of 60psi using a Keene Bell bostapump, this will cover ANY power level you can make on upgraded twin turbos and it will be tunable as well within the limits of the Apexi PFC platform.

If you are going non sequential or single turbo buy a Link G4 plug in and be done with the crap PFC. On my car I run 4 x 1000cc ID1000 (latest generation Bosch fuel injectors) and it idles like a dream (13:1 AFR) and 850rpm and with ~450bhp engine power & 8000rpm it only on 67% duty cycle using 11.4:1 AFR.

Do not use any injectors that require "resistors" this is a garbage way to do things, same for any type of peak and hold drivers etc!, just buy proper high impedance injectors and do the job properly.

[Nik da Greek]

the ones I fitted i needed to shave about 1mm of the injector body itself,its only plastic and files down easily enough,it does not affect the sealing properties. I did it this way so i can always revert back to standard injectors for whatever reason.
The 1680 ones are low impedence injectors and will need the apexi ECU and datalogit to set them up correctly. There has been many a discussion on whether you need the aftermarket injector driver for them but it has been worked out mathematically that there is no need and you should not burn out the injector driver within the ECU.
The clips are different as well but they should come with them and you simply need to splice them into your loom.

I know I\'ve got one of those vulgar FDs so not strictly 100% relevant to the OP, but with my 1680s in a Super 7 rail the guys fitted little ballast resistors just to make doubly sure the loads would remain correct and not damage the drivers in the ECU over time. So cheap and easy to fit it seems mad not to.

Not the best pic in the world, but it\'s the little gold thing just cable-tied to the rail there.

@ RICE, the OP was asking about FCs which AFAIK never had any sort of sequential system

[antnicuk]

im using 1000 cc primaries with a microtec on my series 5 turbo II engine and its ok although the microtec doesnt seem to be the most precis of ecu\'s.  I am running the 550\'s in the secondaries to allow the step up/change over to be much higher up the rev range.

on a side note,  i ran a pfc on my turbo 2 with 1680\'s in the secondaries at 460 fly for 2 years with no problems at all.  I just milled out the stock rail to fit the bosch items,  no resisters used.

[PGiljevic]

:o oops me thought FC = PFC :o

[PGiljevic]

FC type engine, I ran one in my First Gen RX7.

http://www.riceracing.com.au/resources/Zoom-27.pdf

http://www.riceracing.com.au/13B-REW-engines.htm < engine dyno detail on this page (cant direct link picture)

I ran 4 x 880cc "12A Turbo" fuel injectors as they were bolt in the fuel rails ran that to 472rwhp (dynapack hub dyno) around 520bhp or so *probably more* as I am conservative with guessing engine power.

No resistors needed as high impedance and again ran, drove, and was like a std engine.