Make your own free website on

Esprit SE/S4 Memcal Upgrade Information

Many people inquire about upgrading the memcal in their SE or S4 to enhance performance. I have been providing a reprogramming service to Esprit owners in the USA for several years. The memcal is the part of the ECM, or engine computer, that contains the program and data required to run the engine, along with some other circuitry. The program and data (also known as "code") are contained on an EPROM, or "chip", which is soldered onto the memcal, which is then plugged into the ECM.

Please note that I am providing memcal reprogramming as a service to those individuals voluntarily wishing to modify their personal vehicles at their own risk, and can not offer any warranty, refunds, nor accept any liability whatsoever for any harm that may result. I will, however, reverse any upgraded memcal to the original customer code upon request for the cost of return shipping ($15).

Currently there are two upgrade options available, with more coming soon. Option one is the latest revision of the stock Esprit S4s program (Mk V), which adds much improved driveability and an increase in maximum boost. Option two is Andy Whittaker's modified version of the same code, which has been tweaked to eliminate a part-throttle hesitation around 3000 rpm which many people have noticed with the stock S4s chip.


Upgrade Pricing

Following is a price list for the various upgrade possibilities. '89.5 SE's used a chip that cannot be reprogrammed, therefore a new EPROM must be installed in the memcal before it can be upgraded. A socket can also be installed in any memcal to facilitate future chip-swapping. Prices include return shipping within the USA only via insured Express Mail (overnight to most locations).

Upgrade Version '90-'95 SE, S4, or S4s '89.5 SE
S4s Mk V $105 $145
Andy Whittaker modified S4s $230 $270
Moto-Concept SE/S4 TBA TBA
Moto-Concept S4s TBA TBA
Install socket, additional to any upgrade $95 $55



Shipping and Payment

To upgrade your memcal, please follow these instructions carefully:

1) Contact me via e-mail at with the date you intend to ship the memcal and your desired upgrade option(s). I will confirm the date and the amount via e-mail. Please do not ship your memcal without my confirmation, as I do travel occasionally and would not wish to see a fellow Esprit owner deprived of his or her car for any longer than necessary!

2) Remove the memcal from the ECM (see instructions at the bottom of this page).

3) Pack the memcal securely in a well-padded box with a money order enclosed for the required amount and your return address, and ship it insured for $500 to:

Sanjaya Vatuk
1130 Beloit Ave
Forest Park IL 60130-2306

If possible, please e-mail me with carrier and tracking information. Airborne Express is preferred, but FedEx and USPS are acceptable as well. Upon receipt, a safety copy of your original memcal program will be made, the memcal will be reprogrammed, and it will be shipped back via Express Mail by the following business day.




EPROM Chip only Pricing

The following require that you either already have a socket installed in the memcal, or you possess the required equipment and skills to desolder the existing EPROM and solder in the replacement. To order, send a money order for the indicated amount to the address above. You do not need to send your memcal. Orders will be shipped via Priority Mail. Please add $15 for shipments outside the USA.
S4s Mk V, EPROM only $50
Andy Whittaker S4s, EPROM only $175
Moto-Concept SE/S4, EPROM only TBA



Memcal Removal Instructions

Here's how to remove the ECM from an Esprit SE or S4, and the memcal from the ECM.
Click on any photo to see a larger image. Pictures should appear in a new browser window.

Before starting the ECM removal, disconnect the negative battery lead from the battery. Remove the engine cover, then remove the six screws securing the carpeted trim panel from the right side of the engine bay. Some cars may be missing one or more screws.

Carefully remove the trim panel by pulling it sideways then lifting slightly upwards.

Locate the two nuts, each securing one side of the ECM to its bracket (yellow arrow). Loosen,
but do not remove the nuts from their studs. If the ECM is to be removed from the car, squeeze the connectors as indicated by the green arrows and wiggle all four of the connectors free. Lift the ECM upwards to remove it.

Locate the access panel on the bottom of the ECM and remove the four screws using a 1/4" nutdriver. If the ECM has never been serviced, there will be one or two pieces of anti-tamper tape along the edges. Slit at least one piece to gain access.

The memcal is the blue object pictured above. To remove it, press down on the latches as indicated above...

As the latches move outwards, the memcal will pop out of its socket.

When reinstalling the memcal, note the small bump, or key, along one edge of the socket.

Locate the corresponding notch in the socket. Carefully position the memcal above the socket and guide it into position. Push down firmly and evenly until the latches click into place. Reinstall the access panel and its four screws.

Reinstall the ECM into the car, being careful not to dislodge the mounting studs/nuts. The flat washers should be fitted between the mounting bracket and the nuts. Reconnect the four plugs, noting that they are color coded as shown above. Carefully reinstall the trim panel, being sure not to tighten any of the screws until all of them have been started. Reconnect the battery.

Copyright 2000-07 by Sanjaya Vatuk

Updated on 03/11/07


Get Firefox!