MoTeC produces a number of engine management solutions to meet the needs of a wide range of users. This is a guide to help you choose the most suitable system for your application, however, we advise you to discuss your requirements in detail with an authorised MoTeC dealer prior to making a purchase.
WHAT DO I NEED?
The first consideration should be the number of inputs and outputs required to run your engine and any auxiliary equipment. The engine requires outputs for ignition coils and injection drivers, and auxiliary outputs can be connected to fans, pumps, lights, or perhaps a turbo wastegate solenoid.
Take into consideration both the modifications you may wish to make now and any additions you might want to implement in the future. It can be sensible to choose an ECU with spare inputs or outputs that can be used for functions and devices that are added later.
If you run a modern engine with continuously variable camshaft timing or a drive by wire throttle system you need to choose from the MoTeC ‘hundred series’ ECUs, which all provide control capability for these functions.
Maximum Versatility or Dedicated Control?
In addition to our range of flexible ‘gold box’ ECUs, which can be configured to many applications, MoTeC has a number of dedicated systems to suit specific engines. These models may prove cost effective and can simplify ECU selection.
WHAT DO I WANT?
All MoTeC ECUs have data logging available as an optional upgrade which includes the use of i2 Standard data analysis software.
Logging rates, memory and flexibility depend on the unit you choose. The ‘hundred series’ ECUs offer the most advanced data logging capabilities, allowing for individually selected channels to be logged at different rates ranging from 1 to 200 Hz. With the addition of a beacon, the ‘hundred series’ ECUs also allow for track mapping. The Pro Analysis option is available on the M800 andM880 ECUs which enables the use of i2 Pro for data analysis.
To assist with initial tuning, all MoTeC ECUs include six or eight hours of free logging and wideband Lambda. This is based on the first hours of engine running time.
Selected ECUs have a Telemetry upgrade available to enable transmission of live data from the vehicle to the pit where it can be viewed in real time. To convert telemetry data into a log file for analysis with i2 software, the Remote Logging upgrade is required.
Engine control units communicate with other electronic devices via either RS232 or CAN. MoTeC ‘hundred series’ ECUs are able to communicate on both, while the earlier generation units communicate solely on RS232. Some modern devices like MoTeC’s Shift Light Module only communicate on CAN and consequently may only be configured on the ‘hundred series’ ECUs.
The MoTeC ‘hundred series’ ECUs use Windows-based Manager software, while the earlier generation models are managed via a DOS interface. Authorised MoTeC dealers are skilled in both, but it is worth noting that the DOS-based Manager software is no longer updated with new features.
HOW MANY INPUTS DO I NEED?
Main Engine Inputs
To determine engine speed and load conditions and to monitor the engine, a basic engine will require:
- Crank/cam position—Ref/Sync trigger input
- Throttle position—analogue voltage input
- MAP, manifold absolute pressure—analogue voltage input
- Engine temperature—analogue temperature input
- Air temperature—analogue temperature input
MoTeC ECUs are compatible with most common crankshaft/camshaft triggering systems (Ref/Sync modes).
Many of the modes are generic to a particular system or vehicle manufacturer and cover a wide range of applications. However, with the development of variable valve timing, some Ref/Sync modes are specific to one particular engine or family of engines.
Some modern triggering systems may only be available in the ‘hundred series’ ECUs. Typically these applications would also require the additional functionality and inputs and outputs these ECUs provide.
Your MoTeC dealer will be able to tell you which Ref/Sync mode your engine requires.
All ECUs have various types of additional inputs that can be used to suit your requirements:
- Analogue voltage and temperature inputs, used for sensors such as oil pressure, fuel pressure, oil temperature, gear position
- Digital and speed inputs used for wheel speed measurement, activation of dual RPM limit, over-run boost, air conditioning etc.
HOW MANY OUTPUTS DO I NEED?
Basic Engine Specification
The type of engine (rotary or piston) and the number of cylinders will be the basis for the number of outputs you require. The ignition and injection modes with which you intend to run the engine will dictate the exact number of injector and ignition drivers needed.
- Sequential mode
Injectors are wired with one injector driver per cylinder and each injection event is precisely timed to the engine’s firing order. Sequential injection allows cylinders to be tuned individually with end of injection timing to maximise the performance, efficiency and refinement of the engine.
- Group fire mode
Injectors can be grouped together with each group wired to one injector driver, reducing the number of outputs required. For example, a twelve cylinder engine can run with six groups of two injectors, reducing the number of outputs from twelve to six. Group fire mode reduces the precision of fuel timing and it does not allow for individual cylinder tuning.
- Hi-Lo or secondary injection mode
Each cylinder is wired to two injectors, requiring two injector drivers per cylinder. A typical installation would consist of one set of injectors located close to the inlet valve and targeted at the back and the second set located upstream in the inlet port.
- Coil per cylinder
Each coil provides the spark for one cylinder and is wired to one ignition driver. The number of outputs required is equal to the number of cylinders.
- Wasted spark
An engine with one coil per cylinder is wired up with two coils on one ignition driver. Two opposing cylinders in the firing order receive a spark at the same time. One cylinder will be at the right position to ignite the mixture, the spark in the opposing cylinder will be wasted. Many cars are wired this way from the factory and have coil packs specifically designed for this purpose. The number of outputs needed is half the number of cylinders.
A distributor makes the spark from one coil available to all cylinders. This mode needs only one ignition driver.
- Distributor per bank
Some V6, V8 and V12 engines have two distributors; one per bank of cylinders. These engines require two ignition drivers.
Auxiliary outputs are used to control devices such as fuel pumps, shift lights, boost control valve, idle speed control valve, drive by wire throttle motors, cooling fans etc. Some devices also require specific sensor inputs to operate correctly.
On MoTeC’s M800 and M880 ECUs, spare injector and ignition outputs can be re-configured as extra auxiliary outputs.
If the ECU does not provide enough inputs and/or outputs for your application, expander units can be used to increase the total number.
Expander units are available for several functions, for example: