Specifications

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Bank to Bank
Multipoint - Bank to Bank - Multipoint is the least efficient electronic method of injecting fuel into an engine. Each injector is physically located in a position
which allows its fuel output to be delivered to a single cylinder, but the fuel is injected once per rev and injection timing is of no real value even if the ECU is
synched to the engine's cycle because an entire bank of cylinder's injectors are fired at the same time. The advantage of Bank to Bank is that the ECU typically
does not need to be synched at all. This makes it a simple retrofit to engines which never used crank or cam triggers, because it can run the engine with simply 1
pulse per cylinder firing. Ignition timing can still be adjusted, but it is required that the engine use a mechanical distributor to distribute spark from 1 coil. No
individual cylinder trimming is possible.
Individual Cylinder Trim
When an ECU is synched to the engine's cycle, it becomes possible to individually adjust a cylinder's ignition advance and also if the engine is full sequential, the
amount of fuel which is supplied to that cylinder. MoTeC allows individual overall trims of each cylinder's ignition and fuel quantity in all models. In the M4 and
the M400/600/800, Individual cylinder trim tables are provided which allow the tuner to vary the timing and the fueling based on RPM and Load. Typically fully
variable ignition advance requires the use of multiple coils to avoid rotor-tip to cap-terminal alignment problems which may lead to spark scatter. Additionally if
a single inductive type coil is used, it is possible if high fluctuations in advance occur between cylinders, that the coil does not have sufficient time to charge
which leads to reduced coil output energy and possible misfire.
Bank to Bank
Singlepoint - Singlepoint involves placing the injectors in a single common injection point in the inlet path. This is typically done on roots or screw supercharged
engines and some normally aspirated engines. This provides the least efficient method of using Electronic Fuel Injection. About the only method which provides
less control is Carburetion. From a power standpoint, single point is not tremendously worse. Fuel consumption is typically significantly increased over any of
the above methods. There is virtually no control possible as far as each cylinder is concerned and the inherent problems of delivering 2 substances with differing
mass through the same passages an into the combustion chamber are present. The advantage of Singlepoint is that it does not require the ecu to be synched in
any way. MoTeC makes an attempt to smooth out the fuel delivery of singlepoint by triggering the injector drives in a staggered manner. This provides a
smoother more consistent delivery of fuel and reduces the instantaneous drain on the battery/charging system which can lead to ignition misfire in other
systems.
Narrow Band Lambda
Narrow Band Lambda provides an output voltage between .1v and 1.0v dc based on the oxygen differential between the exhaust pipe and the atmosphere. This
can give an indication of the air fuel ratio at which the engine is running however the sensor range is limited to ratios of about 14.0:1 (1.0v) and 15.4:1(.1v). At
ratios beyond this range, the sensor output does not increase or decrease making it virtually useless for tuning an engine for anything other than steady state
cruising. The advantage of Narrow Band Lambda comes into play while trying to keep emissions in check. The sensor provides a signal to the ECU which
basically indicates either rich (output voltage above .5v air fuel less than 14.7) or lean (output voltage below .5v air fuel greater than 14.7) but really does not
describe to what degree the mixture is either rich or lean. This is fits perfectly in with the need for "perturbation" of today's 3 way catalysts which need excess air
to catalyze Hydrocarbon and Carbon Monoxide, and excess fuel with which to reduce Oxides of Nitrogen. Because of this requirement by the catalyst, Narrow
Band Lambda Control is constantly varying the air/fuel ratio both slightly above and below 14.7:1 in such a manner that the average air fuel ratio is maintained at
14.7:1. Most engines in use today, produce peak power with air fuel ratios in the 12:1 - 13.5:1 range well below the measuring capability of a narrow band lambda
sensor. It is for this reason that Narrow Band Lambda is of no help for high loads and or RPM's.
Wide Band Lambda
Wide Band Lambda provides the ECU with a specific definition of the air fuel ratio at which the engine is currently running. Wide Band Sensors are able to
depict air fuel ratio's as rich as 10.5:1 and as lean as 18:1 and report the exact lambda to the ECU. This is done a number of ways. MoTeC M4 and M48 ECU's
use Bosch 4 wire Wide Band Lambda sensors to measure wide band lambda. MoTeC M400/600/800/880 ECU's use either the Bosch LSU or the NTK UEGO
5 Wire Wide Band Lambda Sensor. MoTeC then uses this information to determine the actual lambda and displays this on the console and or uses it for Lambda
Control if the ECU is set up to do so.