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1990's Morgan plus 8 (Hot wire injection models)


It all starts with re-chipping.

The unique Rover V8 engine, has been used for the 'Morgan Plus 8' application for many many years, Essentially it was borrowed from the Rover P5/P6 model, to 1976, Rover SD1 models to 1986, Range Rover Classic models (carb to 1989, Flapper injection to 1989, Hot wire injection to 2000 & Sagem (Gems) injection to present date.
The understanding here, is, An Engine built & intended for other vehicles with different load/weight characteristics from its intended use, means efficiency, power, and engine correctness is always compromised in its Std form.

With early carb models, this was not much of an issue as they could be easily re-jetted and the igntion timing reset to take care of things. With the later fuel injection types (EFI), it is also very simple but does require changes to the ECU ( chipping) regarding engine management system upgrades
Therefore we have put together this special 'Morgan Plus 8' page to help show, not only the essential chipping changes required but also the other external upgrades that are simple to fix, quick to do that will give some quite stunning results

The Hot Wire Air mass meter.

This picture shown the Type and position of the 3.9 & 4.6 Air mass meter, this shows that this vehicle is the 'Hot wire injection' type.

Therefore the information contained within this page is correct for this type. or Morgan normally 1990 to 2000 models

Why Re-Chip anyway?

If the engine fitted is not originally designed for your car type.
An essential basic upgrade for any Efi engine to gain economy and efficiency.
When converting to a large capacity & performance tuning,
Lowering engine combustion temperature. & avoiding engine block cracking.
For maximum engine economy, efficiency & reliability.
For maximum engine life & cleanest emissions.

Morgan Plus 8, ECU. identification and location !!

Simply locate and remove the ECU, It is fitted under the passenger side dash ( (RHD models) and is removed by locating the '2' 8mm retaining bolts, release these, then disconnect the large electrical harness connector.

Socketing, if yours is not socketed Then we can provide the socket to install or you can send the ECU in and we will take car of it. for you. (see below).
If your's is socketed Then it is a simple job to remove the 'Lucas' cover & fit the Optimax or Tornado chip. as per the supplied instruction's. this is indeed very simple to do.
Software variants, There are only two known software variants, 'X36' approx. 1994 and newer, 'X22'Pre 94.
You however need not worry about the difference between these. But we will need to know which it is so that we can be sure to supply you the correct Optimax or Tornado chip for you type.

Optimax or Tornado? (power level choice's)

The Optimax chip. has been designed for all Std and mild tuning on the 3.9 Morgan only, it will add substantially increase economy, Throttle response will become far more crisp & responsive idle will be smoother with enhanced pulling power to your vehicle, and in most cases is the ideal upgrade,


The Tornado Chip. Essentially the same fuel profiles as the Optimax with more top end and revised fuelling for the bigger capacity engines such as 4.6 and beyond (without loosing sight of efficiency) Whichever one you choose, you are going to be pleasantly surprised by the huge gains achieved by such a quick and simple upgrade. the following are some of the superb advantages obtainable. the following information will demonstrate just how simple the process is

Further understanding of fuel maps!!

What makes our Morgan Chips different?
ECU Chip and scrambler.

Full control of the fuel map is contained within this innocent looking Eprom (Chip) It contains all the fueling rpm & fuelling Load Map information and instructions require to run your engine. We have unique plus 8 variants to suit all road and race needs

Most tuning companies will seek to poor moor fuel into the top end rpm, purely to gain some more Bhp, mostly so high up the rev range you'd hardly notice it on a V8, These engine drive almost entirely on torque so it is important to provide them the most efficient fuel map throughout the entire rev range, Both Tornado & Optimax provide for better economy, more torque and Bhp through smoother idle and help to keep combustion so clean that you engine will survive for years, This is so important on Morgans that tend to do very low mileage but get older in the years.

When you demand High & Higher load performance, such as under hard acceleration and load pulling the Optimax and Tornado will run richer and give you the best possible performance both without loosing sight of efficiency With over 120 load/rpm adjustments, the Optimax and Tornado are streets ahead of any competition. (most of which just target more bhp with more fuel dumped in at thigh rpm)
When you are in part throttle cruise driving The fuel mixture using Optimax or Tornado will run slightly lean giving you the best possible economy

Further modifications almost as essential


It beggars belief that with a car as valued & unique as the Morgan Plus 8, even brand new ones are supplied with plug wires, no better than would be found on a Std Land Rover,
Although they are made by Lucas, the quality would relate to that of basic speaker wires on a very cheap hi-fi perhaps. So It leaves little to explain that upgrading them to a seriously good quality plug wire can have some pretty dramatic results.
lets face it no matter what you do to your engine its not going to work properly if the combustion is poor. due weak spark output. This is why we recommend supply and use Magnecor ourselves.

Magnacor plug leads 

Magnecor Street & Race Wires. both Magnecor KV85 Competition (8.5mm) and R-100 Racing (10mm) Ignition Cables, are used extensively throughout the world by leading racers and performance minded street vehicle owners to maximize the efficiency of their vehicle's ignition system.

Magnecor Road & Race Wires are the only ignition wires that can carry the full output of racing ignition systems while providing superior EMI suppression for electronically managed engines and superior heat resistance. Trumpets 

Unlike the majority of ignition wire brands that have proliferated the performance market in recent years, Magnecor Race Wires are not just branded cheaply constructed generic spiral conductor ignition wires that most performance parts promoters like to include in their product lines to sell through speed shops and mass-merchandisers in the USA.

We now have a full range of "Magnecor" V8 Rover leads in stock, For all Morgan models. ( 1969 - 2003) , Both the superlative KV85 range, & the less expensive *8mm Street wires". An essential addition to any performance or efficiency seeking engine.

We fully understand many plug wire manufactures claim the earth from gimmicks, special materials and extra silicone, however the only wires that really work are those that have a spiral core winding around the centre core thus collapsing high resistance caused by the magnetic field when carry voltages as high as the igntion is required to '30Kv' plus,
Measuring resistance in a Plug lead when it is not carrying igntion voltage does not prove a thing for quality only diagnosing dead ones.

Coil Pack  

Although this coil pack is from the Later Morgans 2001- 2003 they clearly show the problem with stock and high resistance plug wires,

The coil tower indicated and the one next to it are completely burn this is because the voltage sent down the cable was offered high resistance and found it easier to short to the cylinder next to it.

These coil packs cost in excess of £400.00 so it would have been much cheaper to change the Plug wires to quality ones long before this happened.  

Ignition upgrades & distributor checking

For further details on the igntion (click here for our igntion section)

There are so many variants of the igntion systems fitted over the years the Morgan mostly offering severe compromise to spark output. typically the worst are the earlier systems especially the points model. this also includes those that have been upgraded to Luminition as the quality of these older units cause mechanical dropout and with such small @dwell' output is still very much lower than it could be.

Where to Start,

{short description of image}First remove advance vacuum pipe from intake and check for positive vacuum when throttle is applied.
{short description of image}Check if (fitted) that the vacuum delay module is not blocked.
{short description of image}Check positive vacuum will pull distributor advance whilst also checking vacuum module is not holed. (when sucking the pipe, the base plate of the distributor should rotate anti-clockwise about 15 deg.)
{short description of image}Check condition of rotor arm for signs of damage or arcing, also check cap and clean contacts ( better still fit new)
{short description of image}Check rotor for free play, there should be none, both rotationaly and side to side.
{short description of image}Check rotor will turn clockwise through about 20 deg, and smartly retract back to it's home position under good spring tension.
{short description of image}Distributor output is known to be weak so upgrading with our Spark amp is recommended. (see below)
{short description of image}Replace plug leads, preferably with Magnecor. Use good quality Plugs such as NGK BP6ES, avoid fancy plugs, as they don't normally last long.

By going to the relevant page link above you can read up on all igntion issues, but here we are assuming your distributor is in great shape and your main wish is to promote the strongest spark output for it,

A&R Igntion pre-amp   Hand built A amp
Installation is less than 30 min.'s. without any experience.   Small on the outside, Big on Power on the inside.

Our Unique A&R replacement amplifier designed to give maximum igntion output.

With so many UK and EU vehicles converting to LPG. ( propane) the weaknesses in the Std. spark output of even the latest V8 distributors has always been an issue,,.( LPG is 104 octane) We decided that the problem would need to be addressed and we invented this neat little amplifier to do just that.

To keep it simple it is best to understand that all Rover distributors have been designed to reduce the charge voltage by 50% half way through the dwell period, (clearly visible on an oscilloscope) this in turn means that about 30% of possible spark output is compromised.
The only reason we can think for this is by doing so Rover have increased the reliability of the small transistor found their stock amplifiers, buy reducing its work load. This does not bode well with the way we see things so we have designed our own Pre-Amplifier that enjoys 100% charge time, thus restoring the output back to maximum.
Other advantages is our unit is simple to repair if failure ever occurs whilst all Rover ignitions Pre-amps are throw away. You can even retain your original Std one for if you ever need to go back to it.

The Adjustable fuel rail pressure regulator

There are two main players/ controllers of the fuelling of these Morgan EFi engines. We have already discussed the Chipping issues now it the turn of fuel pressure, but first a quick overview is required

Chipping allows us to play with injector pulse lengths electronically and control the fuel mix by lengthening the pulse or shortening depending on engine load/rpm requirement, the downside of this can be, If you fuel rail pressure ( delivery pressure) is low, the ECU will struggle to provide a long enough injector pulse and fuel rail pressure will then be lower,

Installing the adjustable fuel rail pressure regulator allows you not only to step up the rail pressure & to relax the ECU & fuel pump, it also ensures enough pressure is supplied & available for the injectors to provide the best injector spray pattern, essential for clean and efficient combustion

   Fuel pressure regulator line up.

Show here are many variants of the fuel rail pressure valve. it essential to have adjustment, as the Std has has no such ability thus no guarantee of correctness.A very low cost essential upgrade that gives you adjustment & control otherwise denied to you completely.

Injection system simple hardware upgrades
For further details on the igntion (click here for our igntion section)

Whilst we have many higher levels of injection hardware upgrades, you will see from the following pictures just how badly the stock engine is severely suffocated the engines ability to breath thus robbing it of existing, let alone its maximum potential.

To view the full range of upgrades we can offer visit our injection pages, by following the above link.
Below however you will see how a simple upgrade to our 'Superflare trumpets' cannot fail to make significant gains in basic engine efficiency
The Rover engine fitted with the stock intake hardware.

Std plenum chamber

   Our Superflare trumpets are easy to fit to your existing intake.

Trumpets or velocity stacks

This is the Stock plenum chamber as fitted to all EFi's since 1982, although the injection types may have changed the Hardware is still the same as ever, even with the bigger variant engines including the 4.6 The plenum retains the same size throttle diameter, the trumpets are the same tall design and very narrow and the intake manifold tracts are the same bad casting as they have ever been.


On the left you can see the original trumpets as fitted to all EFi V8's for the past 20 years,
It comes as no surprise that reducing the Air flow restriction into the engine has substantial additional power advantages it also proves how little has been done to achieve superior power levels for these more modern engines, even for the larger capacity variants

Rogue's Gallery
For further details on these vehicle's (click here for our projects section)

Like most Morgans we have seen, This one is a credit to its owner(s). As you will see the "Engine", itself is in great shape due to good & regular oil changing regime. However the combustion inefficiencies are obvious.

Plus 8

Even though very low mileage, Under 30k, this Morgan was suffering from to many, too short journeys,

Although it sure doesn't Show it on the outside

Chipped plus an RP4 cam upgrade with Stage 1. heads, This Morgan has not only take's on a whole new lease of life but its prolonged it by many many years too.!!

  So now to
the bad news..

Take 1 very clean V8 & look closer.

Close up of the head Gaskets
It shows just how much compression must have been leaking almost everywhere. Moreover the valves, combustion area & head faces show just how badly and inefficiently this engine has been running.

Luckily this is, 'not only all too common' but very easy to fix too..

  New heads etc.

Its always the same

Here, we have another very low mileage Plus 8.

Showing exactly the same problems, This is common with all Morgan plus 8's that where equipped with all Fuel injection types, Thankfully the solution is very simple and 100% guaranteed too!!.

Smile its a Morgan

It is true that Morgans get some of the greatest care in the world, Indeed most are very low mileage and serviced regularly,
The biggest problem is, with such poor combustion the engine contaminates itself from within, No matter how many times a year you change the Oil, you will never stop the internal cylinder contamination unless you address the weakness in these engine's when fitted to such a lightweight car. Notwithstanding this there is so many power and efficiency to be easily gained too.


With the top end removed
, You can see just how clean this original engine block is. We have not cleaned it all so that you can see the real issues going on inside

  Original engine is in great shape esternally

Contaminated Piston crowns


So now to the bad bits..

A closer inspection of all the Pistons show's a life of very poor efficiency and crude Incomplete combustion.

This is not indeed a fault of the owner, When a basic Range Rover engines is fitted into a lightweight vehicle like the Morgan than things cannot be expected to be so efficient,

When a engine oozes. torque. who notices anyway. Well we do and you deserve it. It is so easy to sort out from as little as Cam change, fuel re-map and appropriate engine tune. So why sell yourself short.

Its not only Road cars that suffer, Highly modified's are severely missing out too.

Tuned for race and Street use.

Its not only street spec. we cater for.
There are many Morgan Plus 8's, with highly modified, high performance engines (not excluding full race) models out there some with extensive engine performance mods, running with Std fuel injection trim or poor quality compromises. this amounts to the same as driving a highly modified race engine with Std carbs and Std needle /Jet combinations, as you could imagine this would never work.

We have been involved with so many hundreds of upgrades to all model Morgan plus 8's we offer a full 100% parts refund policy if your are not 100% delighted. with our products.
below you can find some customer comments from around the world

Customer comments

Info on chipping Location, identify etc.

Fuel computer 14CUX   ECU Label

This label, located on the ECU top-cover will indicate ' part no'. and 'date', info, please make sure your is 14CUX type and Not> 14CU, As it is not possible to chip the '14CU' variant. Fortunately however this type is not common on Morgans except NAS models.

Pictured, with the lid removed !!
ECU already Chipped

All Done !!!. This ECU had already been re-chipped, (lower centre left) & has a yellow sticker on the top, it is shown plugged into our scrambler (Supplied). Both intern are plugged into the ECU's Eprom socket

  shows socketed & covered eprom plus identity chip location

This ECU points out the Lucas cover over the original Chip and also identifies the chip that you need to read the part number from ( see below) this ECU type is easily chipped yourself as all types with this Lucas cover are already socketed.

Close ups !!
ECU with Lucas cover

This close up, shows The plastic Lucas cover hiding the chip, this at least denotes that your ECU is already socketed, The top arrow is pointing to the chip that denotes the software variant within it's part number. (see below)
This type is 'Plug & Play'

  ECU not socketed

This is the (now) rare alternative often found on early Morgan models, You can see there is no black plastic Lucas cover, as the Eprom (the one with the white sticker) is clearly visible & is soldered directly into the main board.
This type will best be sent in for socketing.

And now 'Even closer'. !!
Close up of software chip

Close up of chip, denoting
software variant's

  The part number of this chip (its the square one above the main fuel chip) denotes the software type that your Morgan has,

It is still quite simple, read the part number, on the top of thew chip If it has the letters 'KA' this indicates the later variant (X36) software, Otherwise and with any other numbers it is for sure the earlier type (X22) software.

You need not worry about the differences, but do we need to know what variant you have to supply you the correct replacement chip

For the more Technical? Or those who just need to know more.

One way of instantly detecting if your ECU is unhappy is to watch the Rev counter at idle and start-up, because, if the ECU cannot cope with things or does not understand it will hold the revs a little high ( it has its own air valve to achieve this) it then makes adjustments before settling down to the best idle it is capable of,

You can be sure all is correct when the ECU no longer needs to do this continuously

A new EPROM chip must be fitted the same way round as the one it replaces, or else it will probably be destroyed (fry and die!). The decoder board and the EPROM chip are marked with a red paint spot by pin number one, in addition to any manufacturer's markings. If you look at the socket on the circuit board you will see that that also has a notch at one end, which identifies the pin one end. However we have seen the sockets fitted incorrectly in the circuit boards, so the most important thing is to pay close attention to the way the original EPROM was fitted.

Now reassemble the case and stick the provided label onto the outside of the ECU case.

Refit the ECU into the car by reversing the removal procedure. When the ignition is turned on for the first time without starting the engine, the fuel pump will be heard to run for three seconds and then stop. This is a good sign at this stage!

It is recommended that you retain the old chips and covers, and keep them in a safe place. This may be handy if you wish to retain the chips when you sell the vehicle, or in case the original ECU fails and needs to be exchanged one day (although they have proved to be exceptionally reliable in service so far). Please note that the chips cannot be replaced if you exchange them! Remember that the chips are still vulnerable to ESD deaths so please take care when handling them.


It is important to understand that the Hot wire system is adaptive, and it will "learn" how to manage the engine over the first 20 miles or so. The rest of the process actually continues all the time you drive, this ensure the ECU will adapt itself completely to the most appropriate situation, so knowing this it is essential to have all other settings correct with timing, air mass meter, & throttle potentiometer Etc

When the new chips are first fitted, there will be a small improvement in performance which is noticeable immediately, but the real benefits will not be observed until a couple of hundred miles have been covered.

Tornado series EPROM chips provide full diagnostic capabilities, which are fully compatible with the Land Rover Test-Book and Autologic diagnostic systems.


Due to the complexity of the Lucas-Sagem GEMS system, the chip upgrade should not be fitted if the vehicle has any existing engine faults. If in doubt then it is best to visit a dealer who is equipped with a Land Rover Test Book or Autologic diagnostic system and have the vehicle checked over. This is strongly recommended even where there is no obvious fault, although in 95% of installations there will be no problems.

If you have problems then don't panic! Your supplier can help you here. Most of the mistakes you can make have been made before. Just be honest and then we can help you. If there is any problem with the chipset then it will need to be returned for inspection before it can be replaced.

1. The fuel pump either doesn't run for three seconds, or runs continuously when the ignition is turned on. Oh dear. At least one chip is probably plugged in the wrong way round, or one of the legs is bent underneath, or the ECU has been damaged during the process, or the EPROM/ECU is not plugged in yet.

2. I plugged in the EPROM chip the wrong way round and realized after I switched it on. In this case it is almost always the EPROM chip and/or the decoder that is damaged, not the ECU. The best thing to do here is confess, and a replacement can be issued at a reasonable cost upon return of the dead one. Both the EPROM and the decoder contain unique signatures that are destroyed by incorrect connection.

3. The vehicle is difficult to start, or runs poorly. This type of behavior usually means that there are fault codes in the ECU. It is most likely that this behavior was apparent before the chip upgrade was fitted. However in certain cases the upgrade can expose or highlight a previous fault. The cure for this is a visit to a dealer equipped with the Land Rover Test Book or Autologic diagnostic system.


When working with GEMS vehicles. Never try to locate a misfire by pulling plug leads off - pull the injector connector instead. Otherwise you can blow up the ECU.

. Secondly never swap ECU's between vehicles to test them, because both vehicles and ECUs may stop working, and you'll have to have them all reset by a franchised LR dealer (ouch!).

links to other component pages
[ V8 engine and component information and pricing ] [ Back to:Carburetion & fuel Injection ] [ Electrical ]
[ Transmission 2wd & 4wd ] [ Suspension, Handling, Tyres, Wheels & Brakes ] [ Stainless & Mild steel Exhaust systems ]

Prices do not include local EU.Tax.(VAT).
Prices & stock are subject to change without notice. Information and advice, as always, is free.

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