Ev6 injector upgrade

(Vikram Ambrose) #1

I’m in the process of a DIY EFI conversion on a V12 E-type. I got some rebuilt 19lb EV6 injectors (Bosch 0280155702) pretty cheap thinking it would fit the XJS manifold I sourced for this project, but it doesn’t seem to be a perfect fit.

The O-ring recess in the manifold only appears to be 5mm deep, so the O-ring retainer seems to interfere with the O-ring seating all the way.

Can I just remove these things? Since there is already a machined step from 10mm to ~13.7mm, there is no way the 14mm O-ring would slip into engine.

Some rough measurements of the injector boss in the manifold;

|    <--16.7mm-->    | 2.5mm
 -                  - 
  |                |   5mm
  |  <--13.7mm-->  |
   -              -
    |            |
    | <--10mm--> |  6.35mm
    |            |
 ====            ====

O-ring crush appears to be about 1mm (~0.040 in). Which is a tight fit but should be fine.

Found a few references to people running without the retainers on E38 BMWs without issue.

What do you folks think?

I’m completely new to EFI and learning in the process.

(Kirbert - author of the Book, former owner of an '83 XJ-S H.E.) #2

I know nothing about these things, but just looking at those retainers, I wouldn’t think those are engine parts. I’d think they were packaging.

(Vikram Ambrose) #3

Yup they look pretty ridiculous for where they are situated in the engine. But on some engines the injector boss is just a straight hole and the retainer prevents the o-ring from slipping into the intake.

(Matt Furness) #4

I think that looks pretty good without the plastic retainer. The system only has to seal about 15psi of vacuum. What is the outside diameter of the end of the injector…so how thick is the annulus that the o-ring would have to extrude through to enter the manifold?? If…say …the gap was 1.5mm between the outside of the injector and the 10mm hole then the force extruding the o ring into the gap is only about 1 pound weight. This is not much …so I think the o ring will stay put. You are also clamping the injector into the hole somehow so this will help keep the o ring in place.

(John) #5

Jaguar used special rubber seals for sealing injectors into the intake manifold. If you remove this plastic retainer and o-ring I think originsl sealing ring can be used.

(Vikram Ambrose) #6

That looks like a nice form fitting seal. Could you please post a part number for these seals?

(Paul M. Novak) #7

The Jaguar part number for the fuel injector “Lower Mounting Ring” as detailed in the Jaguar Parts Catalogue for my wife’s 1990 XJ-S convertible (5.3L V12) is EAC2415. I don’t know if these will work in your application but I can’t see why they wouldn’t.


(Vikram Ambrose) #8

Does anyone have a PDF copy of the engine/fuel system parts book that they could upload here or PM me?

(Paul M. Novak) #9


I only have the hard copy versions of the Parts Catalogues for my Jaguars and don’t know where .pdf versions can be found.

I regularly got to the Jaguarclassicparts.com website to look up parts. You could try that to see if it has what you need.


(Vikram Ambrose) #10

Apologies for how nasty these intakes look but it looks like with the o-ring retainer removed, the injector o-ring seats well into the manifold.

It would be nice to close up the gaps around it so maybe one of the original o-rings may work for that.

(bdragon) #11

If you’re up for some fabrication, you can buy fuel injector bosses that can be welded into that manifold designed to fit the injector of your choice. The very first search hit I got was this (no recommendation, just showing what’s available: https://www.efihardware.com/products/c86/Injector-Mounts-and-Bosses)


(Matt Furness) #12

That looks like a good fit!! I would fit one in and apply full vacuum to the other side if possible and see what happens. If there are any witness marks on the o ring…or any signs of damage then it’s a “no” . But I would be surprised if there were. O rings are very effective seals at 2000-3000psi if designed correctly. At 15psi …one hundredth of this pressure…the inherent strength of the o ring seal geometry should be sufficient…I don’t think the O ring will extrude through the small gap between the injector outside diameter and the hole in the injector boss.
I am going to do this mod with my XJS and have the high impedance injectors already. Where did you source the fuel rail extrusion??

(Vikram Ambrose) #13

I’m thinking of ordering the “Dash 6” extrusion from Ross Machine Racing via Ebay.

I would have preferred to use steel square tubing but I’m too busy with other things to cut and weld all the bosses, so the extrusion just needs to go into the drill press and should be done quickly.

(SD Faircloth) #14

I am a bit late joining this thread. Do you realize all of the 5.3 liter HE V12 engines used low ohm (2.4) injectors? All of the fueling electronics on those engines are designed for the low ohm injectors. What is the plan for that ?

SD Faircloth

(Matt Furness) #15

Normally an aftermarket ECU . Mine is a megasquirt.

(John) #16

Funny thing is that part number for these rubber seals didn’t change, but their design did. EAC2415. But now with this part number even Jaguar supplies simple square rings which don’t seal that well as more sophisticated older design. I can supply you these seals if you’re interested, just send me a message.

(Kirbert - author of the Book, former owner of an '83 XJ-S H.E.) #17

That intake manifold was designed for Bosch injectors so the seals are a standard, not a Jaguar design. Typically they were sold in a set that included the large rubber mounting ring. Here’s a set:


IIRC, when I did this job years ago, I bought three kits of four cylinders each.

(John) #18

Yes these are simple standard square rings, but this is not what Jaguar used from the factory.
The one on the left is the old seal that came from the factory and one on the right is what you get in most of the kits nowadays.

(Vikram Ambrose) #19

If anyone has an original Jag injector on the table, could you measure the outer diameter of the bottom O-ring? I know these are all “14mm” O-rings but I think there is quite a bit of variation.

I’m thinking of drilling out the intake side to 14mm (0.55in) or 13.89mm (0.547in=35/64in) and maybe another 0.125in deeper. This way I can keep the O-ring retainer. Not that its necessary but I just don’t want to rip all these new retainers off my rebuilt injectors :slight_smile:

(Kirbert - author of the Book, former owner of an '83 XJ-S H.E.) #20

Do you believe those retainers can hold up to engine temperatures? Like I said, they look like packaging in the photo. If that’s what they are, they’ll probably be a molten glob by the time the engine reaches operating temperature.