There were several available in past, I believe. I was under impression there were even conversion kits sold with everything needed to get rid of distributor and control EFI and ignition with programmable ECU.
What choices we have today, if any?

 

google electronic control units,, almost endless list.

i use SDS,Simple Digital Sytems, lately MS ,Mega Squirt is popular,, something important is how much support will be available on line, plus reviews ,and a forum!

some can be very expensive , like anywhere from $500., to $5000, and more, depending what you need ! something to consider is Dyno tuning after install.

the self tuning ones are nice to a point,.
my SDS i couldnt do without NOW, that i got it setup correctly. its N/A, forced induction is a completely different story,, especially when engine goes from vacuum to pressure in manifold.

altho its a great learning curve.

 

I have ThunderMax on my bike. Wide-band oxygen sensors, auto-tune. Works great. It is a plug in replacement for stock ECU. I was hoping there is something similar for V12. Now I see it is going to me more like a Lego project.

 

Where from do you get the trigger impulse? I don't think my car has a sensor I could use - when distributor is removed.

 

pic of distributor, optical sensor , Crane electronics, NLA.

 

OK, so you still have distributor. I'm thinking getting rid of it and using COP (coil on plug).

 

now you are talking a completly different story, big bucks before you will be done!

there is very little quick conversion parts for Jag V12s.

 

The last couple years of 6.0 V12s used distributorless ignition...but it wasn't C-O-P. Maybe there's some hope in exploring that? I dunno; not in my realm of experience.

Megasquirt seems popular but I'm under the impression it takes quite a bit of time/effort to dial in.

If you don't mind my asking, what's your goal or motivation for considering an aftermarket set-up? If you're after DIY tune-ability then I reckon it's the only way to go. OTOH, the stock system also works well and if you just want a few ECU tweaks, Roger Bywater can fix you up easily....and surely with less expense and effort than a complete conversion.

Cheers
DD

 

My motivation ... I'm the tinkering type. And this original EFI/Ignition probably was state of art 30 years ago, but there has been huge development in this area. When I fitted ThunderMax to my bike I got both - better fuel economy when cruising and more power when I open it up. As an added bonus the engine runs cooler, too. I really believe the auto-tune works well for street use and needs no corrections from operator.
Look at COP, simple, reliable, not even very expensive, I've seen these $25 each.
To sum it up, I'd like to see the same effect on my XJ-S. Better mileage when cruising, a little better power at full throttle. Better engine protection against overheating, easier diagnostics, etc.
That said, my project is in dreaming state right now. Once I've figured out what parts I need and how they all work together I can move forward. May not happen soon.

 

Really funny... I haven't been on this board in a few months, but I got on here today looking for ECU solutions, and I found your string here. I have an '89 TWR that I recently converted to a Getrag 265 5-speed with my 5.3L V12.

A couple years ago, my Brit ex-pat mechanic recommended that I contact AJ6 Engineering in the UK. Its principal, Roger Bywater, was the chief engineer responsible for emissions systems at Jaguar in the 1980s. He designed/coded the ECUs originally installed in the XJ-S. He sells something he calls a "Super-enhanced ECU" for the XJ-S. He claims it improves fuel efficiency and horsepower. I communicated with him for several months before purchasing because I wanted to make sure the ECU would not affect my emissions and that I would continue to pass California smog tests.

So Bywater assured me it would pass smog here. I bought a used ECU from Just XJS (eBay site, based in UK), and had its proprietor (Andy) ship the ECU to Bywater for re-programming. Bywater won't give you a new ECU, you have to send him yours or a suitable substitute. I didn't want to be without my original ECU, so I bought the used one, a 16CU, I believe, to be compatible with my car. He programmed it and shipped it to me. He said he would provide special mapping for the Getrag 5-speed manual. All told, I was about $750 in with the new core, reprogramming and shipping.

I put it in my car last October when I finally had my transmission conversion project completed. It ran terribly with the AJ6 Engineering ECU. Ran super rich, flooded the engine, hesitating and gurgling and missing all power. I complained to Bywater, who offered no real suggestions for adjustments. I returned the original ECU to the car and it ran fine, although not super exciting. Manual transmission makes it a totally different car, the OEM ECU ran fine with the 5-speed, just not extraordinary.

I complained to Bywater that his ECU did not work. I suggested to him that his ECU was improperly programmed. I asked him to examine it. I spent $150 shipping it back to him in the UK, he charged me about $150 to check it and ship it back, but he told me "nothing was wrong with it, it must be your car." I researched other boards and found another board where a guy bought a Super-enhanced ECU from AJ6. He described symptoms very similar to mine and said he fixed it by subbing out his old throttle potentiometer for a new one, saying that the OEM ECU didn't rely on its feedback as much as the SE-ECU does. I emailed Bywater and asked if the throttle pot might be the key. He THEN tells me that would be the first thing he would have checked, along with the O2 sensors. I directed him to ship it back to me. I finally got it back early July. In the meantime, I ordered a new throttle pot and O2 sensors from Barratts to install. My mechanic did all that for me, got the throttle pot adjusted precisely. The AJ6 SE-ECU still didn't work, doing the same thing.

So now I have $1,000 into this Super-enhanced ECU and it doesn't work. I'd like to find a way to make it work in my car. Open to suggestions as to what other adjustments I may need.

 

how you gonna use COP on Jag V12 HE, take a close look at the plugs , not much room for a GOOD coil !

OH well keep dreamin !

crank position sensors are easy up front ,, but cam position ,whould be to machine a hole on frt of cam chain box .

anything can be done ,only takes time and money,or maybe reverse order!

ron

 

Actually, there is more space than most COP equipped cars have. Look here for instance: Set of 6 for $40

​​​​​​​Edit: 1A and 1B may require a little extension or installation under an angle. Maybe not. I'm sure I can build little brackets to secure them to the fuel rail.

 

Too bad my car has no oxygen sensors. Means I need somehow to install them, such a system without wide-band sensors is not feasible. Feedback is what helps to tune for economy and performance. Also, sequential injection helps with fuel economy. The only part that will cost $$$ is the ECU itself. Some of these ECU's are sold with all sensors needed to run them. Need to dig into this, there are too many.

 

It's easy to add O2 sensors, just weld a bung onto the pipe. You might want to search for Philip Lochner in South Africa. He has done the megasquirt conversion to a few V12's , as well as adding the coil pack ignition. For the V12 ignition he had to design his own circuit board to run the second bank, as there nothing commercial that can run 12 cylinders.

 

There are units that can run 12, but they may bee too freakin expensive. Motec for 12

 

Another one which can run 12.

 

when you get it up and running let us know , pix would be great also!
ron

 

It depends. If I get the stock system running then motivation drops, I suspect. Right now it is not running well and if it comes to buying parts for old system then I'd spend money better on something modern. It is a challenge and when it works then there is that little thing what is called satisfaction.

 

Might be worth looking into Ferrari V12 aftermarket ECUs to, as some share the same ign system. I keep seeing the name Marelli Marvel12 but have yet to find a definitive place to BUY one. Or there is this link

 

I would forget COP too many hassles and they fail, my mate (BMW 540) keeps a spare COP in the boot for when one fails.

I have got MegaSquirt installed into the Jaguar case which will plug into the OEM harness in the boot. Because MS uses PWM for injector control; you have spare wires in the harness to run low current ignition to the engine bay.

Easiest way to do ignition is to use Ford or GM 6 cylinder coil packs. Trigger can be done on damper with a 36-1 wheel and VR sensor. MS3 can also run V12 sequential although there is not much point in this except for emissions and fuel consumption.