Hi
I am looking for a set of fuel injectors for a 1999 XJR, with better flow than I have at present.
book shows part number as LCC1521AD
also listed for the 4.0 litre naturally aspirated is LCC1521AF
They are physically interchangeable,
Without me purchasing one of each, would anyone know the fuel flow rates.
Cheers

 

Hi dc4prez,

I can't tell you about X308 injectors, but I researched XJ40 and X300 injectors and learned that the XJ6R injectors have a fuel flow rate of 380cc/min, compared to 220cc/min for N/A X300s. See my photo album below for more details:

Welcome to Jag-lovers - Members Photo Viewing Page

Do you plan to make other modifications to your system to accommodate the increased fuel flow rate of new injectors? Have you considered cleaning your existing injectors? Below are photos of the method I used at home, which yielded an increase in fuel economy of 2.67mpg on our '93:

Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page

Cheers,

Don

 

AJ26 XJR/XKR injectors flow 355-360cc at 43.5PSI. AJ27 injectors 5-10cc more.

 

Thanks Don - Thanks Sami
Don, the vehicle is over 600HP
Twinscrew supercharger, 3 1/2" cold intake
twin 2 1/2" exhaust, Abaco MAF,
oversized intercooler radiator
Flowed and CC'd heads --- and more
Hi Don
reason I need bigger injectors is that I keep blowing up blocks at high RPM
it is leaning off I am running somewhere over 75PSI fuel pressure, I need to know that I can supply the fuel.


Thanks Sami, mine are the side entry type, yours should be too. I have been advised to make a fuel rail to suit top entry injectors, I am not that dedicated --- Maybe Andre is listening -- good project
Cheers and thanks guys

 

Here my injector results at 2.5bar.


Below are flow test results prior to cleaning the injector pintles. Tested at 2.5 Bar, 60 second flow rate. full open (static test).

1) 320 ml
2) 320
3) 317
4) 317
5) 320
6) 316
7) 316
8) 309

Average flow 316.88 ml
Low 309
High 320
Spread 11 (low to high)
Deviation 3.41 %

The deviation should be 3% or less. In your case, the deviation is 3.41 %. Due to injector # 8. All the others look good.

I only ultrasonically cleaned # 8, as the others looked good. After ultrasonic cleaning #8 is at 316 ml.

Now your specs are as follows....

Average flow 317.75 ml
Low 316
High 320
Spread 4
Deviation 1.79 %

They all now look good and ready to refit.

 

Dave, you just need bigger fuel pumps or KB BAP. 75PSI is too high for stock Densos and their flow capacity drops. Stock injectors are ok up to quite high hp numbers. The another problem is that based on the tests done the stock injectors start to leak at high PSIs. Already at 65PSI.

 

The KB BAP worked perfectly for me. But I was only at 470 to 480 HP with my Eaton

You say you "keep blowing up blocks" How many have you blown?

 

Hi dc4prez,

600HP sounds like a jolly good time! Hope you can resolve the issues so you can enjoy all that power.

Cheers,

Don

 

If you have a 4.2 why don't people just copy whatever AVOS did, since his works perfectly at over 600 hp?

If you have a 4.0, then copy Steve M, didn't he just use a larger secondary pump? He still has the fastest proven XJ here.

 

Mine has a Kennebell S/C fitted, possibly more mods than Avos"s until recently,
I understand what you are saying, It's - or will be a 4.2 block, with 4.0 internals, Mine is built to a blueprint - flowed and CC'd heads,
I do have a BAP, still in box.
If you remember, you commented on my dyno about 6 months ago, about how lean it was mid range. (how much torque for little HP)- which was wheel spin on the dyno
This time round I am looking at a piggyback system, to take control of everything. xjr99 has good things to say about Vipec, their Parent company D-link is probably the one I will use,
Cheers
Dc

 

Right, Steve M has the KB as well and ran 11.9, so 550+ HP on his 4.0
AVOS has more mods than just the KB TS, cams, etc + who knows what


Wheel spin on the dyno at approx 600 hp.....that should not happen. I've witnessed 900 hp dynos with no wheelspin.

Do post about the ECU improvements, that will be helpful for all those who go the way of the Twin Screw