Dual EDIS-6 support for V12?

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jagwit
Posts: 5
Joined: Mon Oct 30, 2006 12:14 pm
Location: South Africa

Dual EDIS-6 support for V12?

Post by jagwit »

Hi all

I've installed a Dual EDIS-6 igntion system on my Jag V12 knowing that the SAW phasing for the B-bank edis module would not follow after the PIP falling edge but be close to the PIP rising edge.

I made a bench setup which seemed to work OK but on the car it does not seem happy (above 4000rpm) and I fully suspect the B-bank EDIS module is not happy with the SAW signal its getting not being phased correctly.

Current setup uses Megasquirt-2 for spark and fuel. EDIS A sends PIP to MS and the SAW from MS goes to both EDIS modules.

Any MJLJR suggestions for my dual EDIS setup?

For more info: http://www.msruns.com/viewtopic.php?t=20086
Kind regards
Philip

Land rover Discovery S1 4.6 V8 (Megasquirt-2/Fuel & EDIS)
Jaguar XJS '80 5.3 V12 (Megasquirt-2/Fuel & dual EDIS)

brentp
Site Admin
Posts: 6282
Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

Hello,

I've been discussing this with another V12 owner. Clearly, as you have identified, you want the SAW pulse to follow each EDIS module's PIP pulse.

I was thinking a possible solution would be an external circuit to flip-flop the SAW response between the two EDIS modules.

In other words, EDIS-A sends the PIP signal, which latches the flip-flop to send the SAW response back to EDIS-A; when EDIS-B fires it resets the flip-flop so the SAW pulse sends it back to EDIS-B. The MJLJ would see it as a EDIS-6 running with 2X the PIP pulses.

However, I would like to know if the PIP pulses overlap in time. Have you traced the PIP pulses from both EDIS modules on an oscilloscope? seeing the PIP pulse relationship between modules would be useful.

Regards,
Brent Picasso
CEO and Founder, Autosport Labs
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jagwit
Posts: 5
Joined: Mon Oct 30, 2006 12:14 pm
Location: South Africa

Post by jagwit »

Hi Brent

Scope traces here:
http://www.jag-lovers.org/snaps/snap_vi ... 1174581954

Pic 1 is the two PIP signals from EDIS A and B.
Pic 2 is what EDIS A is seeing (and what EDIS - B should be seeing) - no problems here.
Pic 3 is what EDIS B is seeing (SAW clearly coming way too early)

So, we need a circuit that will delay the SAW pulse until the PIP-B's falling edge.

Kind regards
Philip

jagwit
Posts: 5
Joined: Mon Oct 30, 2006 12:14 pm
Location: South Africa

Dual EDIS solution!!

Post by jagwit »

The Dual EDIS-6 based ignition system is now working perfectly in my Jag.

The short version is that I implemented a "SAW delay" circuit which memorises the last SAW pulse width, waits for the falling edge of the PIP pulse of the second EDIS module and then transmits the SAW pulse to the second EDIS module.

The whole story is here: http://forums.jag-lovers.org/av.php?949015m52 (you may have to search for the rest) and here http://forums.jag-lovers.org/av.php?966641o15

The nice thing about the concept is that it will also work for MJLJR implementations!

Kind regards
Philip

ewout
Posts: 7
Joined: Fri Apr 20, 2007 12:21 am
Contact:

Re: Dual EDIS solution!!

Post by ewout »

jagwit wrote:The whole story is here: http://forums.jag-lovers.org/av.php?949015m52 (you may have to search for the rest) and here http://forums.jag-lovers.org/av.php?966641o15
Unfortunately non-registered Jaglovers cannot see the content...


BTW what Jag and why have you converted it? Just being curious. I did have a Daimler Double Six SII once with L-Jetronic... I still regret parting with it...
Transit Mk2

jagwit
Posts: 5
Joined: Mon Oct 30, 2006 12:14 pm
Location: South Africa

Re: Dual EDIS solution!!

Post by jagwit »

ewout wrote:Unfortunately non-registered Jaglovers cannot see the content...

BTW what Jag and why have you converted it?
I did not realise that unregistered users can not see the content but if it is important to someone, just register, not so? It is a bit frustrating as there is no single place where I can document the whole project complete with pdf, jpg, and txt attachements - at least, I have not found it yet.

I have a '80 XJS Pre-HE V12 5.3 10:1CR which started life std (as they all do) but the OPUS ignition system started it all by packing up when hot. My search for an electronic alternative brought me to Megasquirt which in turn brought me to other things like EDIS and WBO (which made me realise how rich the car was running) and how I could fix this if I took control of fuel injection, which I did.

So now I have a Pre-HE squirted by MS-2, ignited by Dual EDIS-6, electrical fans, upgraded Bosch 100A alternator, 5 sp Tremec gearbox etc.

The whole story here (hoping that unregistered users can see the content): http://www.msruns.com/viewtopic.php?t=20086

Kind regards
Philip

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