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. e advantage of Bank to Bank
is that the ECU typically does not need to be synched at all. is 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 se-
quential, 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. is is typically done on roots or screw
supercharged engines and some normally aspirated engines. is 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 typi-
cally significantly increased over any of the above methods. ere 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. e 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. is 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 atmo-
sphere. is 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. e advantage of Narrow Band Lambda comes into play while trying to keep emissions in check. e 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. is is fits perfectly in with the need for “perturba-
tion” 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. is 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.