INSTALLING A NEW CHIP TO A HOTWIRE PLUS 8
by Lorne Goldman

WATCHPOINT: Non-Morgan North American Hotwire systems do NOT come with an easy facility to accept new eprom. A harness must be bought and soldered in..preferably by a jeweler or computer specialist

Consult the documentation that comes with your new chips (s).

Firstly, any automobile ECU,  even more so than a normal computer, can be easily damaged by static electricity. To avoid these problems, computers are normally worked on in specialized environments which reduce the possible of a destructive charge. If you are not working in such an environment, you can reduce the inherent risks by grounding the surface you are working on. For example, you can use a metal desk or a sink top draining area or use foil on the surface you are using. Wear natural fabrics rather than synthetics as well.

1. Have your old chip and engine checked out a dealer with a diagnostic unit to make absolutely sure there are no pre-existing engine faults. Ideally you will have a prgramming unit (GEMS) or at least a Code Reader (GEMS and HOTWIRE) of your own.

2. After you have your work area set up, disconnect the battery. This makes absolutely sure that the ECU is completely unpowered.

3. Pull the little spring clip and gently pry it off the ECU.

4. Unscrew the larger screws (normally at the corners),  that hold the ECU onto the car and pull the ECU from the car;

5. After you place the ECU on your grounded work area, unscrew the screws holding the lid to the ECU. (5 screws on a Rover).

6. The circuit board is now visible and may be released by unscrewing the screws that hold it in place (6-8 of them)

7. In the Plus 8s, HOTWIRE and GEMS, the chips are fitted in sockets.

N.B. On the HOTWIRE Plus 8s, if you have a label on your Eprom (chip), it is a socket type but if the Eprom has no label you will probably have to buy a socket attachments and install it for your new chip.

N.B. Newer GEMS Plus 8s also have two "chips". One is blue plastic (the larger one) and the other is green each with a Lucas stamped on it..which will overwhelm you with confidence.

The cover must be removed by gripping it in the middle with long nosed pliers. Wiggle the cover gently from side to side to release it from the circuit board below. When loose, the chip itself may be removed by carefully levering it up and out using a small flathead screwdriver between the Eprom and its socket.

Take extreme care not to bend the pins of the old EPROM as it releases. Be equally tender with the chip socket and the circuit board at all times.

8. Note to the orientation of the chip or chips as the new chip must be fitted the same way exactly as the one it replaces. If this is done wrong, you will probably destroy the new chip at ignition or soon after.

N.B. With the GEMS Plus 8s, the green decoder board and the EPROM are marked with a red paint spot by pin number one. The Eprom socket on the circuit board also has a little notch at one end which identifies the pin one position. PLEASE NOTE however that Lucas has been known to fit the chip sockets incorrectly so pay close attention to the way the original chip was fitted and you should be all right.

9. Carefully orient and slide the new chip into the socket making sure all the chips' pins enter the socket without a problem. It is very very easy to have a pin fold underneath while inserting. Use a magnifying glass if necessary to get this right. After alignment and first entry, a good firm press will be required to seat the devices in the circuit.

10.  Now reassemble the ECU casing and label the outside of the ECU with the new chip type you have installed.

11.  See HERE if there are any problems.
 

N.B. ALWAYS KEEP YOUR OLD EPROM CHIPS!!! Remember the problems and dangers with static electricity and store the chips appropriately.

11. 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 for a few seconds and then stop. 

WATCHPOINT 2: For the HOTWIRE Plus 8s  please note that the chip is adaptive to small degree. It "learns" how to manage the engine over the first 30-50 miles. Additionally, the Tornado chip is more sensitive than the stock chip and may make your engine trouble light go on. If this happens, check if you have an installed Fault Code Reader behind the glove box or buy one and installed it.

SIGNS OF A PROBLEM INSTALLATION

A. The fuel pump doesn't run for a few seconds, or runs continuously when the ignition is turned on. This means that at least one chip is probably plugged in the wrong way round or ( more rarely) one of the chip prongs is bent. Alternatively, the ( UGH!!) ECU has been damaged during the process, or the EPROM or the whole ECU is not plugged in.

B. The EPROM was installed the wrong way, you tried to start it and it fried. Both the CHIP (and with Rovers the decoder) have unique signatures all their own which will both be destroyed in this situation and are then useless. Normally you can make a deal with the chip supplier if you own up and return them.

C. The engine is hard to start and/or or runs badly. This normally indicates that the ECU is registering fault codes...which   have been present before the new chip was installed. This should have been noticed and dealt with before (see the beginning of this article) but occasionally a new chip can aggravate an existing fault. Find a dealer with a diagnostic unit and that should help.

D. No improvement in performance could mean you have installed a poorly designed or wrong chip.

OPTIMAX VERSUS TORNADO CHIPS

WATCHPOINT:These are well known chips, programmed by Mark Adams, that have become a standard within the Morgan community and beyond. I can recommend them and they will allow the purchaser to stay within Morgan community lore. However, they are misunderstood. The Tornado programming became very popular with racers of modified engines and he named his chips for the later GEMS fueling by the same name though the Tornado for the Hotwire and the Tornado for GEMS have nothing to do with eachother and cannot be swapped for one system to the other.  

FOR HOTWIRES

Optimax Chip The Optimax and the Tornado are pretty much the same. Optimax is a slightly cut-down version with the only difference being a high revving continuation of the same fuel map. It is more than sufficient for the standard Morgan 3.9 installation and a waste of money otherwise. It should be considered if you have done other improvements, a fast road camshaft, better quality and higher flowing injectors, better air induction, porting, a bespoke exhaust system and the potent power enhancements you can find on this site OR if you are doing an engine swap to a 4.6 or bigger. Sadly, many moggers buy it because they are poorly advised by other, not very knowledagble owners. There is not much knowledge about these things in the Morgan community and the forums are not what they used to be. :( What you can expect is cooler engine running, more acceleration, better mileage. I do not find the Optimax on Mark's site, (October 2020) but that could just be me. Mark used to offer an exchange of a Tornado for an Optimax for the cost of the difference in price.

The Tornado Chips

FOR HOTWIRES

The same as the Optimax chip above, but with a higher programmed rev range. 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 losing sight efficiency). If you do have a capacity change, please note that Mark has chips programmed for the 3.9, the 4.2 and the 4.6. If you get the wrong chip (s) you will never know the full value of the eprom. If all goes well, you can expect is cooler engine running, more acceleration, more power released, better mileage.


FOR GEMS

These are TWO (2) chips that come as a set for the later GEMS Plus 8s which became the standard in 1998 in the USA and Downunder, and in 2000 for balance of the classic Plus 8 era worldwide. They are also wise for another reason. The GEMS Plus 8s can exhibit many anomalies in their Morgan factory format. These probelms can be cured fitting Mark Admas chips along with re-installing the missing antiknock sensors. These chip sets also come in 4.0/4.6 and capacities greater than 4.8..

It is understood that the information contained herein is offered without any
undertaking whatsoever and no warranty is suggested or may be implied.

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