The ME221 MX-5 PnP from Motorsport Electronics is the latest generation of plug-n-play engine management for the Mazda MX-5.

An ME221 standalone ECU gives you or your tuner complete freedom to get the full potential out of an MX-5 engine block. The fuel and ignition tables are easily adjusted, and a host of safety and motorsports features are built in.

When do you need an ME221 standalone ECU?

From the factory, an MX-5 comes with a standard ECU which controls the injectors, ignition and a number of peripheral functions. If your MX-5 is all original then this one will probably suffice.

Once things like a turbo conversion, circuit use, supercharger conversion or other things come into the picture, which cause more stress or give the potential to create more power then you can’t avoid a standalone ECU like the ME221.

With any modification to the engine of the following, it is important to install an ME221:

• Turbo/supercharger
• Injectors
• Ignition

Why can’t I use the original ECU?

With the example turbo conversion or supercharger conversion, a standalone ECU is hugely important because many times more air goes into the engine which the original ECU cannot measure. This results in a so-called lean mixture; the ratio of air to fuel is far too large and can cause major damage to the engine.

An ME221 ECU allows a tuner to see exactly how much air is entering the engine and adjust the fuel tables accordingly. This ensures that the engine gets enough fuel to make good use of the extra amount of air. With this larger mixture of air and fuel, there will also be more power. This is why a turbo conversion always requires replacing the injectors for larger ones as well.

Beyond fuel tables, there are also ignition tables. These tables control when the spark plugs spark and ignite the mixture. These must also be adjusted to ensure that the engine relates the mixture optimally and no damage occurs.

Safety and motorsport functions in the ME221 ECU

We have talked before about possible damage to an engine. The MX-5 ME221 ECU contains various functionalities that in many cases can prevent damage by, for example, shutting down the engine when oil pressure is low. Listed below are the most important safety features:

• Pingel/knock detection
  Pinging or knocking is a phenomenon where the air/fuel mixture ignites before the ECU controls the ignition. The mixture ignites by itself. Pinging can cause major damage to the engine such as holes in pistons.With a knock sensor and the ME221, it can be set up for the ECU to immediately adjust tables to make sure the engine stops pinging.
• Flex-Fuel
  When power is high, people often switch to an E85 fuel. The ME221 can handle this and even measure the ratio of E85 to Euro98. A tuner can use this to ensure that if E85 is not available just Euro98 can be filled up.
• Custom functions
  It is possible to link sensors, tables and variables and write rules for them. For example, if the oil pressure is too low, it is possible to shut down the engine, if the coolant temperature is too high, it is possible to reduce the maximum speed and many more functions that ensure safety.

Also considered are track drivers, drag racers and those doing turbo conversions. The following motorsport functionalities can be found in the MX-5 ME221 ECU:

• Boost control
  With a turbocharger, pressure can be adjusted in several ways: wastegate adjustment, manual boost controller and an electric boost controller. Boost control allows the ECU to send a signal to the electric boost controller, this makes it easy to set the turbo pressure via the laptop at the tuner.
• Interchangeable maps
  A 160hp map for the wet Dutch days and a 260hp map for on the track or when it’s dry? The ME221 ECU can transform your MX-5 from civilized power to maximum power with the flip of a switch.
• Launch Control/ 2 Step Limiter
  Set the optimum speed where the least wheelspin occurs. If you stand still and the clutch is depressed then launch control will be activated and you can maintain the set RPM even though the gas pedal is at the bottom.
• Anti-Lag
  This feature is mainly seen in rally driving to ensure that the turbo remains maximally spooled.
• Water Methanol Injection
  WMI cools the mixture in the cylinder chamber which can provide better combustion and therefore more power or a safer engine.

Plug and Play

A very big advantage of the ME221 MX-5 ECU is that it is very easy to install. Per model year series, a specific ECU has been developed by Motorsport Electronics which can be mounted on the original plugs in no time.

The Motorsport Electronics website has manuals for assembly and all the settings. Always read these carefully to ensure a successful installation.

Basemaps

A basemap tells the ECU what basic settings are needed for your setup. With a basemap it is possible to start the car and with most of them it is perfectly possible to drive. However, the latter is always at your own risk; Motorsport Electronics and LucaCarMods recommend always having the car tuned by a professional tuner.

A basemap can be found for almost every type of Mazda MX-5 and basic configuration. For example, there are basemaps for an MX-5 Turbo, supercharged or with the original engine.

Large MX-5 air masseter replaced with a small IAT sensor!

What many customers like is that the new technology in the ECU makes it possible to replace the clunky air masseter with an IAT sensor (Inlet Air Temperature). This gives the ECU a much more accurate measurement of the amount of air going into the engine. Often even more important is the fact that it looks much neater under the hood.

Support

There are many different types of ECUs on the market, all of which also offer similar functionalities. Most are slightly more limited in their options but are worthy opponents.

A very big perk of the ME221 ECU is that the manufacturer’s support team is super! If you purchase the ECU through LucaCarMods.com you can contact us for simple questions via our contact form or by phone. If you have very specific questions then you can also put the question to Motorsport Electronics and usually get a solution the same day.

They may also be able to watch along via teamviewer at no charge and assist you with a problem you are facing. In short, you are not only buying an ECU but also a piece of valuable service.

Questions?

Do you have questions following this article? Please feel free to contact us.