does anyone have any leads on where or how i could get my hands on a set of these? please and thank you!

 

There is a guy here in Australia there is info on Ian's website

XJ-SC Modifications

Hope this helps

 

Is there a part number for the Falcon EL injectors he's talking about on that website? Or maybe an equivalent injector for a USA car?

 

Sorry I don't know the part number but the EL is a 4.0L straight 6. There are a multitude of injecttors that you can use. The ones from the GM 3800 would also work these are the same as the injectors for the later Ford.

You will have to tune for any injector upgrade

 

Yes, I was wondering about the tuning too. Would this be a major change? Or just a matter of adjusting the lean/rich adjustment on the ECU? (6-ECU)

 

I think it will need a full tune. The newer injectors have a different spray pattern are larger and designed to run at higher pressure so they would be open for much less time to deliver the same volume.

XJS (edit because of stupid tablet) runs very low rail pressure I think it is around 20psi.

 

That website you posted talks about running a higher PSI of 60 with an adjustable pressure regulator. I was assuming (perhaps wrongly) that the higher pressure increased atomization, with the same flow rate?

 

If you increase the pressure and keep the opening time the same the volume delivered will increase. The XJS ECU has some ability to adjust fueling but not enough to cope with this increase in pressure. Ian runs a Wolf 3D ECU.

 

Hmm...again I made the assumption that if he made it work, the aperture must have been smaller, which would limit the volume of fuel.

Somewhere there must be a graph that tells what the flow rate is on different type injectors?

 

Good luck on this one - I have been looking for reasonably priced higher flow injectors for a while and it is very difficult to find flow rates for OEM injectors.

I have kind of made the assumption if the injectors - say L67 which is the GM 3800 supercharged V6 - can make 400hp from 6 cylinders on stock injectors the V12 could make 800hp with them.

There are other considerations - like the impedance this is the dynamic resistance (AC resistance) as the impedance changes say drops the injectors will cause a back EMF (voltage) to the ECU this could cause the ECU issues if it too large. As the injectors are switched This is an AC current they will act like an ignition coil causing a spike in voltage hence the need for ballast resistors.

 

ouch...I hadn't thought of that...

 

I just shot off an email to that fellow. Hopefully he's still around and can answer these burning questions!

 

So here is the email reply I got. Sounds like he's done his homework!

View full HTML message
Hi Jamey



With my car I have a Wolf computer and many other modifications to the
engine to produce 450HP.



You can change your injection system to aluminium fuel rails and modern
injectors, still driven by the normal computer.



The rails you can buy from Ed Ward edmund.ward@cummins.com



The injectors you can use are Jaguar ones from an XJ40 available from
http://www.ebay.co.uk/itm/JAGUAR-XJS...ET-OF-6-EBC443
0-/200790889046?pt=UK_CarsParts_Vehicles_CarParts_SM
<http://www.ebay.co.uk/itm/JAGUAR-XJS...SET-OF-6-EBC44
30-/200790889046?pt=UK_CarsParts_Vehicles_CarParts_SM& hash=item2ec011d256>
&hash=item2ec011d256



Buy two sets to get 12 injectors. They will fit into the existing manifolds
and into the aluminium fuel rails.



The existing injector wiring as is can be used, I'd just recommend changing
the plugs to the later model Bosch
http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem
<http://cgi.ebay.com.au/ws/eBayISAPI....m=190667144318

&item=190667144318

With the fuel rails, you can get rid of the two pressure regulators, and
install an adjustable one
http://www.ebay.com.au/itm/NEW-RISIN...ATOR-KIT-ADJUS
TABLE-/180523452601?pt=AU_Car_Parts_Accessories
<http://www.ebay.com.au/itm/NEW-RISIN...LATOR-KIT-ADJU
STABLE-/180523452601?pt=AU_Car_Parts_Accessories&hash=item 2a080948b9>
&hash=item2a080948b9



When doing so, run the fuel supply to the rear of the engine and connect to
the fuel rail, and on the rear outlet side mount the pressure regulator then
to the return line.

While you have everything out, I'd suggest you also change the heater tap
from the metal one that rusts and clogs, to one of these plastic ones
http://www.ebay.com.au/itm/Heater-Va...6-2004-/300544
258534?pt=AU_Car_Parts_Accessories
<http://www.ebay.com.au/itm/Heater-Va...V6-2004-/30054
4258534?pt=AU_Car_Parts_Accessories&hash=item45f9d 571e6>
&hash=item45f9d571e6



I am in the Newcastle area if that's handy for you to have a look - but then
again you could be in Perth!

Any other questions, just ask,

Cheers

Ian

Any other questions, just ask,

 

Yes Ian is a really nice guy and very helpful, I have met him a few times at various Jag events around town. His XJS-C is highly modified and does look the business.

 

thats the arraingnment i did in my XJS pre, back in 1995, i used honda injectors(cant rmember what #), custom rails , and XS FPR at the end, all easily available parts, at a fair price.
only thing i do remember is they flowed 21lbs at 43psi, low impedence. there was not much available back then, if i were to do over id use the new small style injector(Bosch).

course you could drill into the head and install DIRECT injection , and run 2200psi fuel pressure, that would probably ATOMIZE quite well. hehe

ron

 

im going to run a holley selftunigcomputer setup and i wanted to switch to a bigger injector when i did this, because im going for bigger intakes and bigger throttle bodies possibly messing with the flow of the intake and doing front or quad throttles

 

A couple of thoughts here.

First I think the quad throttle body idea I would give a miss. It has one major flaw in that it will align the throttle bodies with inlet runner 2 and 5 - not an ideal situation, this goes against all of the principles of not aligning inlet and outlet ports in a manifold plenum. The front throttle idea I like if it were me this is the way I would go. It has the advantage that you can increase the length of the runners for better torque. Although a custom manifold would need to be fabricated.

The V12 as best as I can determine uses 24lb injectors but the fuel system only operates at 30psi meaning the stock injectors will support 400hp at 43.5psi and 450hp at 50psi with an 80% duty cycle. So if they are ok why replace them unless they are working above their duty cycle.

I am also not convinced the XJS needs bigger TB's they are 63mm each giving a total area of 623cm2 which is equivalent to almost 90mm throttle on an LS1. The inlet profile on the TB's is appalling and would definitely benefit from an add on bell mouth. I would not machine a radius on the throttle housing as this will impeach on one of the mounting screw holes creating turbulence. I would find a bolt on bell mouth that fits or is close and modify it.