Technical Information

Below is some technical information that covers the background of remapping, the advantages of a remap, additional options, and the various processes that can be involved.

Midway through the 1970’s vehicle manufacturers started searching for ways to lower the emissions of the vehicles produced. This search was emphasized by the 1979-1980 oil crisis. The search of a way to lower emissions while raising engine performance led to the development of the electronic engine control unit (ECU).

The first ECU’s could control only a handful of parameters and had fewer than 10 sensors on a complete engine. The sensors included crank angle sensors, CHT, 02 sensors, water temperature sensor, and a basic vane airflow meter. These basic setups could lower the emission significantly, but as the years went on, the demand for more complex ECU’s got higher.

Fast forward to the 2000’s and ECU’s now have the capability to control over 50 different modules, actuators, solenoids, and other moving parts. Todays ECU’s have the capability to remain in perfect control of the engine, controlling the emissions in real time, correcting, and constantly adjusting to suit humidity, density, air temperature, and various fuel qualities.

The integral part of todays engine control units remains the software, commonly referred to as the maps. Maps in a ECU are complex and are written to control the engine based on what each map parameters are. The maps consist of torque limiters, fuel limiters, boost limiters, boost thresholds, injector duration, variable valve timing and many, many more. Each of the maps listed above have their own set parameter to keep the engine within the manufacturers set limits.

Manufacturers will set the limits on each map depending on what model of vehicle the car is going to be used in. Manufacturers will always set each limit low, well under what the engine is safely capable of. The reason being for this is to compensate for poor or no servicing regimes, poor quality fuel, extremely hot and/or humid climate, and for longevity of the drivetrain under these poor conditions. Here in Australia, we do not have poor conditions like some third world countries, so engines can safely run at or close to their full potential, which can be achieved by remapping.

At Ecutech Australia, we remap your vehicle. Remapping is a term commonly used among the automotive industry and in simple terms, it means to change parameters and values on the engine maps within the ECU. The maps that are changed are torque limiters, fuel limiters, boost limiters, boost thresholds, injector duration, just to name a few. These maps are changed to allow more power, torque, response, less lag, and better fuel economy.

Maps can be adjusted to suit the hardware on the vehicle. For example, a car with standard hardware would generally run a stage 1 tune, software only. Then take a car with high flow catalytic converter, performance intercooler, and coil packs, this could safely run a high boost stage 2 tune because of less backpressure on the turbo (high flow cat), cooler intake temperatures (intercooler) and less chance of a mis-fire under boost because of upgraded coil packs.

Because of the way the internal combustion engine works, fuel and air are mixed, and then ignited, turning the fuel and air mix into kinetic energy, which then turns the engine. Engines efficiency is rated on a volumetric efficiency percentage, volumetric efficiency is a good determiner of how efficient the engine is. When an engine is remapped, we effectively squeeze more power out of the same displacement, thus increasing the volumetric efficiency.

Increasing the volumetric efficiency not only makes the engine produce more power and torque but will also have the potential to achieve better fuel economy because the engine is more efficient. In most cases however, the engine is running rich from factory, which effectively lowers your fuel economy. Remapping will safely lean this mixture out closer to the perfect stoichiometric mixture which increases your vehicles performance, fuel economy, response, lowers combustion temperatures, and overall engine temperatures.

All this sounds very exiting however with a bad tune written by inexperienced tuners, things can go pear shaped very, very quickly. A bad tune can consist of too advanced ignition timing, injector timing or even incorrect mixture parameters, all of which can cause anything from blown head gaskets to detonation, melted pistons, extreme combustion, and engine temperatures. Considering what can go wrong, it shows the importance of have your car remapped by a professional organization.

Here at Ecutech Australia, our remaps are written by professionals with many years of relative industry experience to ensure the engine produces more power, torque, and most importantly it is operating safely within its limits. This means that your vehicle is in safe hands, not in the hands of an inexperienced tuner that could cause expensive failures further down the road.

Methods of remapping

There are three predominant methods of remapping that we can do, some can take many hours to complete and some can be as quick as 20 minutes, but all methods will eventually achieve the same result, a remapped ECU. When the OBD port was made mandatory for all cars from 2003 onwards, it changed the ball game completely for tuners. Tuners were able to access the engine maps via the OBD port instead of having to bench tune. However, there are still some ECU’s that require the ECU to be opened to access the PC board and/or chip.

OBD remapping

OBD remapping is non-intrusive, efficient and a quick way of remapping the ECU. Remapping through the OBD port allows same results as any other way of tuning, better performance. The original file can be removed off the ECU and then replaced with the performance file. Same process is done to revert to original file at any time if needed.

Bench remapping

Remapping through the OBD port is not always possible for various reasons, vehicle may not have a OBD port, or there may be a firewall put in place by the manufacturer to prevent aftermarket remapping. Tuning an ECU on the bench is when the ECU is removed, and a connection is made via the internal circuit board on the PC board.

There are various methods used for bench tuning and different tools can be used depending on the type of internal microprocessor. BDM, JTAG, Boot mode, and pinout tuning is a way of bench tuning by using a specially designed jig to connect to the ECU by carefully held pins to connect to a separate tuning tool.

Hopefully this helps you in understanding the process of remapping, some history of ECU’s and how ECU’s work.

Glossary

CHT – Cylinder head temperature

02 sensor – Oxygen sensor

OBD - On board diagnostics