Philip Lochner 1980 Jaguar XJS V12 5.3L (10:1 CR)

Philip Lochner · Post by **Philip Lochner** » Fri Mar 16, 2007 1:25 am

Will post a diagram on http://www.jag-lovers.com in due course (will take me a while to draw it ) but in essence, here's how:

The 4 terminal coil pack as two primary coils and two Secondaries. The plug has 3 terminals of which the centre is switched 12V (with a cap) and the terminals on either side are where the EDIS modules ground the coils in order to charge it. A ground terminal fires the two posts on the same side of the coil pack as the terminal.

Coil pack A (in front of engine) connects to cyls 1 and 6 (on both banks)
Coil pack C (in the middle) connects to cyls 3 and 4 (on both banks)
Coil pack B (towards the rear of the engine) connects to cyls 2 and 5 (on both banks).

EDIS module A (for the RH bank) connects to the appropriate pins on the RH side of the 3 coil packs. (Please note that the centre coil pack connector faces forward while the other two faces rearward = see pics) EDIS module B (for the LH bank) connects to the three pins (of the 3 coil packs) on the LH side of the coil packs.

This results in HALF the coil pack being driven by one EDIS module and the other half being driven by the other EDIS module. Clear as mud?

Now, the firing order on the EDIS-6 module is
pin 10
pin 12
pin 11.

Repeat: 10, then 12 then 11.

Coil pack A connects to pin 10 (cyls 1 and 6)
Coil pack C connects to pin 12 (cyls 3 and 4)
Coil pack B connects to pin 11 (cyls 2 and 5)

Studying the firing order of the V12 (1A-6B-5A-2B-3A-4B-6A-1B-2A-5B-4A-3B), the above wiring setup ??should?? now make sense.

PIP of module A goes to MS, SAW from MS goes to BOTH EDIS modules. PIP of module B goes nowhere.

Then all you need are the VR wires (polarity sensitive!!) 12V and Ground.

Voila!

IMPORTANT!! Please note that as of writing this post, the B bank EDIS module was still defaulting briefly to 10Âº above 4000rpm due to the incorrect phasing of the SAW signal for the B-bank EDIS module- which I hope to correct by moving the B-bank VR sensor closer to the A- bank sensor. This may result in the timing on the B-bank being +- 3 degrees early!!!

StevenD57 · Post by **StevenD57** » Fri Mar 16, 2007 6:18 am

Philip:
Have you thought about taking the time to post a note on one of the MS development forums asking about extra code to synthesis that second SAW signal in code for the second EDIS control module?

Perhaps it would not be as difficult as we might thing and would be a quick mode for someone.

BTW, have you registered you car at xjsdata.com yet? I am one of the volunteer admins for that site and others (xkedata.com, xkdatacom, and saloondata.com) and the site owner has just started xjsdata.com not long ago. Would appreciate you being able to register and talk about your unique car. Photos too if you like.

Philip Lochner · Post by **Philip Lochner** » Sun Mar 18, 2007 11:30 pm

StevenD57 wrote:Philip:
Have you thought about taking the time to post a note on one of the MS development forums asking about extra code to synthesis that second SAW signal in code for the second EDIS control module?

Perhaps it would not be as difficult as we might thing and would be a quick mode for someone.

Its done already. Dual EDIS support has been identified as an item for inclusion in the Ms-2/extra products. Only trouble is that it may take 3days - 3 years before it comes out as usable code. This is why I decided not to wait but find a more short term solution.

With MS being open source, if we can just find someone who would be willing to write that bit of code for us we can have a solution in the very short term. Now, if the same guy could make the real time baro "look" at a different A/D port, the current hardware (v3 board)can then support real time baro, dual edis and dual WBO (and IAC stepper motor control for those who want it)

StevenD57 wrote:BTW, have you registered you car at xjsdata.com yet? I am one of the volunteer admins for that site and others (xkedata.com, xkdatacom, and saloondata.com) and the site owner has just started xjsdata.com not long ago. Would appreciate you being able to register and talk about your unique car. Photos too if you like.

I was not aware of this site but will go have a look.

Philip Lochner · Post by **Philip Lochner** » Mon Mar 19, 2007 3:28 am

Attached, a wiring diagram of the dual EDIS setup I have on the Jag.

StevenD57 · Post by **StevenD57** » Mon Mar 19, 2007 7:35 am

Philip:
Thanks for the wiring diagram. Looks good. I have a couple of questions though. What is pin seven on the EDIS modules wired to?

Did you locate your megasquirt box inside the passenger compartment or not? If you did where did you run the wiring harness from the various engine pieces to the megasquirt box? I.E. where in the firewall did you get the wires into the passenger's compartment? I am attempting to wire up some electric radiator fans on my car and I am having a hard time locating some place to run a couple of wires through the firewall into the passenger's compartment for a manual override switch.

Philip Lochner · Post by **Philip Lochner** » Mon Mar 19, 2007 9:04 am

Pin 7 is wired to the shield of the shielded cable running to the VR sensors which I can advise should be shielded. The cable for SAW and PIP is also supposed to be shielded but mine is not and its working fine.

My MS is located inside the cubbyhole! I found a round opening (closed with rubber gommet) on the passenger side of the car (LH side in my case) very close to the blanking plate which closes off the pedal box opening for Left hand drive builds, through which I found a route by placing a torch on the inside of the car. Not a very direct route and not really easy to route the harness through there, but I managed. Then again, is there ANYTHING easy on this car?

StevenD57 · Post by **StevenD57** » Mon Mar 19, 2007 10:47 am

Philip:
I am familiar with low impedence verses high impedence injectors but I do not understand the difference it makes in injector drivers or the solution you eventually came up with to get this working satisfactorily on the V12.

Can you please explain that a little bit more when you have a moment?

Thanks

Philip Lochner · Post by **Philip Lochner** » Tue Mar 20, 2007 1:53 am

I could not explain the issue with low impedance injectors any better than the MS documentation (although somewhat "distributed") but what I can state categorically is that it is vital to
a) switch the injectors using pulse width modulation as opposed to using a high impedance approach using current limit resistors as I've tried, (which increases the opening time of the injectors but also increases the DIFFERENCE between opening times between the injectors which results in great variations between the AFRs of different cylinders at idle and on lean cruise which makes it impossible to get the car to idle leanish - 13.5 - 14 - and to get it to run very lean on very low manifold pressures);
b) install the "active flyback" circuit on Ms-2 and on top of that,
c) that the flyback current be routed DIRECTLY back to the point where the injectors are being fed with their 12V source with dedicated wires coming straight off the respective transistors on the MS board as documented at:
http://www.megamanual.com/ms2/V3trouble.htm (point 16).

Also read the following to understand low impedance injectors better:
http://www.megamanual.com/ms2/V3assemble.htm (step 69) and
and
http://www.megamanual.com/v22manual/minj.htm and as found in (long) this thread: http://www.msefi.com/viewtopic.php?p=15 ... ht=#151591

As was found in the above topic reference, routing the flyback current onto the MS-2 board generates all kinds of volatage spikes on the board itself which causes havoc (presumably not in all cases). I did not even bother to find out but implemented the mod straight away when I realised that the high impedance approach would not be a long term solution.

Others have implemented "flyback diodes" (a search on this term on the forum will reveal MUCH discussion on the topic), wired directly behind the injector connectors claiming that it works as well as the active flyback circuit but I chose not to go that route as I considered that to be MUCH more work than implementing the way I did.

A careful study of the above references should equip you well with regard to the implementation on the Jag.

But, don't be shy with questions!

Philip Lochner · Post by **Philip Lochner** » Wed Apr 04, 2007 2:58 am

Wiring diagram here: http://www.jag-lovers.org/snaps/snap_vi ... 1174304067

Pic of installed system here: http://www.jag-lovers.org/snaps/snap_vi ... 1175449785

Pics of coil pack assembly here: http://www.jag-lovers.org/snaps/snap_vi ... 1170846543

ronbros · Post by **ronbros** » Fri Jul 18, 2008 2:10 pm

HI! came across these posts,on fueling and ignition management. I did something like it back in 1994,i may have been ahead of the curve, my vehicle 1978 flat head V12, 345whp at 7000rpm dyno. Crane race cams, 9.5 comp pistons, for fueling I used SDS management(simple digital systems) made in Canada, fired 3 injectors at each signal,2 inj on one bank and 1 inj on oposite bank. fully adjustable 255 points, has worked very well for 14yrs. triggered the computor from a modified factory distributor, Crane cams and electronics inc. Daytona bch Fl. did the distributor. uses a single hioutput crane coil, and amplfier box. again has worked well for 14yrs also! vacuum advance built into dis. fueling adjustable on the fly, milage 18-20 at cruise 75-80mph, 4 spd auto overdrive GM, 3.73 LSD final. Thx Ron

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Philip Lochner 1980 Jaguar XJS V12 5.3L (10:1 CR)

ask about code development?

Re: ask about code development?

what is pin seven?

Low impedence injector solution

Re: Philip Lochner 1980 Jaguar XJS V12 5.3L (10:1 CR)