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Steve Comet
06-10-2004, 10:16 PM
Many years ago I had a series 3 V12. On very warm days the car would often just die, no warning. I am now buying another 1974, and was told that my old problem was common and that because of the placement of the electronic ignition in the engine compartment a diode would heat up and cause the problem. Now with another 1974 on the way I'm concerned about the problem. I was told that there was a fix -- re-positioning of the unit. Can anyone point me to info on the fix and give me a source for the required parts? Thanks!

Mel Gumpert
06-22-2004, 12:31 PM
I have owned my 74 E since 75 and have had ignition problems (tach would go crazy and car would shutdown). I originally relocated the amplifier from the the original mounting on the block to a piece of aluminum flat bar above the head and in between the cam covers. I did the change in about 77 and it has run fine this way.
Jaguar recognized the problem and Lucas supplied a relocation kit consisting of a new amplifier and pickup with long leads. It mounts behind the radiator on the subframe below the water header tank.

Paul Wiltshire
08-11-2004, 11:38 AM
Sorry this is a bit late - just seen your post! The sudden death problem is almost certainly the ignition amplifier. The (original) location between the cylinder heads caused massive heat build up in the unit and failure is well known. Often, the unit would recover after it has had time to cool - sometimes pouring cold water on it would speed up the process !

There are 2 solutions.

The first is to 'insulate' the amplifier by putting alloy spacers between it and the jackshaft cover on which it is mounted. These need to be as thick as possible, whilst still allowing the bolts to secure it. This reduces the heat transfer from the engine and allows a bit of air flow.

The second, and much better solution, is to buy a modified amplifier kit from a Jaguar main dealer. In the UK this kit is available from the dealer under the 'classic Jaguar parts scheme' It is expensive - around £220 when I bought mine. The kit includes a new (maybe re-conditioned) amplifier, a bracket to position the new unit on the front cross member of the engine frame and the necessary longer cables. Re-positioning the amplifier on the cross member puts it directly behind the left hand cooling fan and, in my experience, fixes the problem. The kit also includes a resistor which was not originally specified.

In case you are tempted, it is not a good idea to move the existing amp. by increasing the length of the existing cables. This will cause other problems. Just spend the money !!

08-12-2004, 08:40 AM
Moving the existing amp is problem free and will not, as the previous post suggested, cause any problems. The v12 xjs had exactly the same issue and they relocated the ignition amp out of the vee and mounted it above the b bank inlet manifold, with a heat shield below it.

10-08-2005, 03:27 AM
In my experience the OE ignition units are not the most reliable, especially not sitting behind the a/c compressor where it is hot. I read a Jaguar bulletin that said to mount it up front on the crossmember and that replacement ignition amplifiers come with a longer harness to allow this. One the last car I repaired, I installed an aftermarket Ignition unit on the firewall above the battery and mounted it on an unused metal piece that sticks out a bit from the firewall, very convenient. The unit I used was 'Lumenition' and it comes with a new coil and optical trigger for the distributor.

Dave Robb
04-15-2006, 09:47 AM
I have a 73 XKE V12 and the kit has been installed on the cross bar behind the radiator fan. My problem is that when the car gets hot, I seem to have a missfiring when cornering and braking... Does not cut off. Seems electrical to me. When I get going and it cools a little everything is fine.

Any ideas out there! I do have an old coil....

06-03-2006, 03:49 AM
LUCAS Opus Type AB3 Ignition amplifier.

The original Opus circuit was an elegant solution to the problems of mechanical ignition points and high revving Multi-cylinder engines.
Unlike today where semiconductor components are designed specifically for car electronics the Opus engineers had to rely on the availability of small selection of electronic parts with which to design their circuit.

Some of the electronic components originally used in the OPUS amplifier will have shifted in value or even partially failed over time and therefore your OPUS amplifier is attempting to operate outside its designed limits.

The OPUS circuit uses the first pulse it ‘sees’ when the ferrite passes the pickup to fire the coil. If the oscillator output frequency or voltage shifts the primary voltage on the Pickup will be insufficient to produce the necessary stable output when the ferrites pass the trigger point in the distributor. When this happens you get a weak and irregular spark, this problem usually appears when the engine is hot.
The OPUS amplifier did not have sufficient temperature compensation or voltage regulation for reliable operation therefore accurate ignition timing was never achieved.

In redesigning the electronics we have kept with the original approach of the Opus team but used state-of-the-art electronics. The circuit still functions in a similar manner to the way it was first designed, except now the ignition amplifier, is voltage regulated and the semiconductor oscillator is temperature compensated. When coupled with the hybrid transistors specifically designed for firing ignition coils this translates to precise timing and a powerful spark every-time.

We have completed a considerable amount of road and dynamometer testing of the REOPUS circuit in my V12 E Type over the last few months to ensure reliability and performance. To date we are more than pleased with the improvement in starting, smooth running and performance using the new REOPUS circuit board. The circuit has been tested up to 6,000 rpm on our test jig and the coil firing observed on an oscilloscope.
The coil waveforms are stable, clean and synchronised to the pickup signal.

The new REOPUS circuit is installed inside the existing Opus amplifier case, it uses the original pickup, ignition coil and existing wiring. To install;
 Remove the amplifier unit from your car.
 Remove the base plate, Remove the circuit board
 Cut the wires from the OPUS circuit as per our detailed instructions
 Fit the new cable plate and install the REOPUS circuit board.
 Solder the 6 wires onto the new REOPUS circuit as detailed in our instructions.
 Reconnect the connectors from the Pickup and the ballast unit.
 We have included 2 diagnostic LED’s on the REOPUS board so you can test the unit to ensure your wiring and static timing is correct before restarting the engine.
 Refit the base plate and reinstall the amplifier module into your car.
Are yuou interested in purchasing a circuit board.

07-16-2006, 01:24 AM
Hi Dave
Moving the amplifier to the front cross member can also cause problems especially if the Pickup lead is close to the Ignition leads this can cause intermittent miss-firing. Apart from the fact you probably have the standard OPUS missfiring. Perhaps it may be worth fitting one of our REOPUS amplifier boards to your existing unit? Then refit your amplifier unit 70mm above the original position with our replacement mounting kit supplied.
If you are interested send me your email address and I will forward to you pricing information.
Regards Dave Curry

09-19-2006, 04:11 AM

09-19-2006, 04:16 AM
After finding Dave's REOPUS unit on Roadfly I bought one and installed it for my 73 E-type OTS. Installing it was easy and the results have been astounding. Better starting, smoother and quieter running and better performance. It's like a new car. And it didn't require any other modifications, even the timing was unchanged. As this is a concourse car I didn't want to go to a non standard unit. Dave, I am one happy customer and can recommend your unit to anyone.

06-03-2014, 10:13 AM
I bought my Reopus "4" in July of 2010. It installed without a problem by my tech. My car is never taken out in the winter or the rain, never washed either with anything other than 3 fresh chamois',auto shampoo soap and then blow dried. I don't think the car was driven more than 2,000 kilometers since 2010. Montreal,Quebec winters are cold,fierce and long and the car is stored indoors and covered from October until May. The battery tender is plugged in. The car has 28,800 miles. In September of 2013 it started doing what it had done prior to the Reopus 4 installation. I thought same was an isolated incident. Stored the car and just brought it out again for service. Took it out for another drive and the Reopus 4 is acting up again. Well, I reported the problem to David Curry who very eloquently explained the problem is with my pickup (all of a sudden!) and if I remove the Reopus 4 assembly with wires and all and ship it to him in New Zealand he'll modify it,add a revised pickup and send it back and this for an additional $202.I paid some 235 pounds stirling in July of 2010 for the Reopus 4.
Although it may sound reasonable, I beg to differ. When I bought the Reopus 4 it was touted as the next best thing to sliced bread!!! After barely seeing any use Reopus has a brand new "fix"!! Also the Reopus 4 as confirmed by David Curry was discontinued in 2012!! 12 months prior to my breakdown in September of 2013 it would have been professional for Reopus to send me a cautionary note that their Reopus 4 was discontinued because of a defect in the seemingly "perfect" Reopus 4. I caution you many new "fixes" at the client's cost and expense can one endure? Either you have a warranty or you don't!! Placing the blame on a defective pickup is not acceptable. I can start my car right now it will run perfectly until just the right temperature and it's back to its old tricks all over again. Either the pickup is defective or it's not!!

This is not acceptable customer service. I accepted to pay for the return shipping of a new Reopus Hall system and same was refused by David Curry.

I then spoke to Mike Glover of SNG Barratt and I ordered a V12 Conversion kit that uses the 1980's Jaguar technology (what I should have ordered in 2010 in hindsight) .Furthermore I spoke to Stew Jones Restorations and Stew confirmed that he had installed at least 50 of these units with spectacular results. Once I have mine installed I will return with feedback.

In closing rather than David Curry sympathising with me about my troubles with his Reopus 4 system he proceeds to tell me "It is obvious that you have a lack of technical knowledge and understanding of what was offered by REOPUS."

And below are just a few of his lengthy responses that tell me one thing...this gentleman is not prepared to put his money where his mouth is.

You ask : What old parts?
I detailed these individually in a previous email.

I was not aware of the OPUS pickup availability at the time you purchased as I had a few myself.
I did the REOPUS H development later and we have not sold a REOPUS 4 for a long time.
I do not have your details and there are a lot of REOPUS 3 and 4 owners who have not contacted us with a problem.

I have started a note for the Forum I am starting on my website.
I have a lot of people who write with various problems, there is a lot of helpful information for other owners.
I thought perhaps your story was worth a mention.
I suggest you consider what you send to any forum.
I have started my reply as below.
I will only publish your name and details if you do also.
My notes to date are as below.
Dave Curry

Suggested REOPUS website forum Page for (
I have found notes on forums on the internet are often written by individuals who are not sufficiently experienced or maybe have "technicians stress syndrome" to write about their problem and often they have not researched the problem and solution correctly therefore avoiding all the facts before they put pen to paper and publish.
For over 30 years I have been helping people solve technical problems.

Recently a customer had a problem with a REOPUS 4 amplifier he purchased some 4 years ago, from his description of the fault I knew from experience that the amplifier would still be running at the same frequency as supplied if it had changed I would fix it no cost, but I knew the REOPUS H is the best solution long term, and I suggested his 40 year old pickup was on its way out and new ones are difficult to obtain.

On our website we suggest our customers upgrade to the REOPUS H pickup and we offer a special price to do this as mentioned on our website.
We offered to supply a new “Hall effect pickup at $110” and upgrade his existing amplifier $70, plus $30 for return freight this was unacceptable to him?

Without doubt his 40 year old pickup was changing its characteristics yes they do go grey over time , but he thought I should replace his original OPUS pickup (not supplied by us) within our 5 year warranty, I ask you.
In one of the emails he sent me he stated he did not think he had the ability to change the pickup. I ask you.
He has gone to another supplier who uses 30 year old technology where our REOPUS H uses 10year old technology and our REOPUS is repairable.

Naturally I can not understand his logic.

This customer decided he should vent his?? on a forum but naturally he will not show all information in the emails he sent me, and all my replies explaining the solution to his problem.

I asked him if he was going to send his misleading information to a forum could I also put the information on my website he said well they will at least know there is a disgruntled customer. is from Canada: Andre Cassis <

On 3/06/2014, at 3:40 pm, > wrote:

I will publish your response along with my comments for all to see and then everyone can make up their own minds. At least they can see both sides of the story and all alternatives available for their cars out there. All they see now is how great and infallible your product is. It would good for them to see that same is not so perfect and that there is at least one disgruntled customer.

I have nothing to hide....if you go to Dave Curry's web site as follows ( you will note that Reopus 4 was discontinued in 2012.

All David Curry had to do is put his money where his verbose mouth is!!! Why discontinue such a great product as the Reopus 4? Oh! Because the pickup is faulty...well make good on your warranty if you discovered a deficiency! Contact your customer!! You where paid by me ...wheren't you? You shipped it to me ? Didn't you? Then when you see a deficiency why pray that I won't contact you? Why offer a 5 year warranty if there is none? Why did I pay some 235 pounds stirling and duty for? I paid it for your supposed knowledge and good faith. The parts are cheap parts anyways! I paid for your supposed knowledge,honesty and integrity and I obviously got absolutely NONE OF THAT.

Fellow Jaguar enthusiasts beware.

06-04-2014, 05:50 PM
It is obvious you do not have the facts.
I do not have your address details as I only keep a name on file.
You are most welcome to send me your amplifier and pickup and can test them.
But I know from experience over the years what the problem will be.
My solution as offered is without doubt the best available.
You are inexperienced and not qualified to make the statements you have been and most of these are personal and misguided.
I will not supply a replacement Opus pickup as they are all old.
I offered you the latest technology including a new Hall effect pickup but it appears you do not understand.
I suggest your comments about me being a back yard mechanic from a person who does not apparently have the skills to use a screw driver and a pair of circling pliers come from a questionable source.
If I receive any further feedback from any source regarding your ? I will forward your emails to your workplace.
They will be addressed to Rainer I am sure he will be upset about the contents of your emails.
My information is only gibberish as you say to an individual who does not understand what is clearly written.
My offer to sort out your ignition still applies.
No more insulting emails please.
David Curry

My response to blackmail attempt by David Curry;

Are you making a feeble attempt to blackmail me to my employer of 25 years? Is this an attempt to protect my employer from the likes of me? I'm trying to protect the public from dishonorable people who won't honor their warranty! Sad actually.

In closing to all fellow enthusiasts be careful of who you are dealing with. I sent my hard earned money to this fellow having a certain comfort level that a 5+ Warranty meant something. When the exact same issue caused by the exact same amplifier occurs and the technology is discontinued is it unreasonable to conclude that a warranty recall should be made and honored? Please don't do as I have done and deal with less than honorable people. The last straw is the attempt at blackmail. How low can one go? Obviously pretty LOW. David...honor your warranty and your product and you won't have disgruntled clients and you won't have to blackmail them to keep their mouths shut.

07-09-2014, 03:05 PM
I received the V12 Ignition conversion kit from SNG Barratt and arranged to have it installed. The result is exceptional smoothness. Stay away from this Reopus exchanges speak for themselves.

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