Rotational Idle

Rotational Idle

Vehicle Functions - Rotational Idle Page


Vehicle Functions - Rotational Idle

Enable Rotational Idle

Activating Engine Demand

The amount of TPS opening for cable throttles, or Accelerator Pedal opening for Drive-By-Wire throttles, below which the Rotational Idle function will be active.

Idle Valve Position

The amount of idle valve opening to be used when the Rotational Idle function is active.

End RPM

When Rotational Idle is active, this is the amount of RPM above which all cylinders will be cut. This should be set to give the engine a stable idle and is typically set a little higher than an amount of RPM the engine would normally idle with when there is no Anti-Lag system.

Cut Method

Select which outputs to cut in order to limit engine speed while rotational idle is active.

Ignition

Ignition outputs will be disabled to limit engine speed. This is commonly used in applications where fuel flow is required to cool the engine.

Injection

Injector outputs will be disabled to limit the engine speed. This is the most commonly used cut method for rotational idle.

Vehicle Functions - Rotational Idle - Conditional Activation

Conditional Activation

Condition Enable

Select whether to enable a particular condition to enable or disable the Rotational Idle Function. This must be Enabled when a switch has been configured in the Wiring Tab.

When Rotational Idle Switch is On

And/Or
Allows an additional condition to be used to enable the Rotational Idle Function, or just the switch input alone.

Select
Allow selection of the ECU channel to be used.

Maths
A selection of Equal To, Not Equal To, Greater Than, Less Than, Greater Than Or Equal To, Less Than Or Equal To that is to be used.

Value
The value the maths must meet.

About Rotational Idle

Rotational Idle is used to maintain a normal low idle speed when a fixed larger amount of air is being used for lift-off Anti-Lag purposes, or you just want to sound like a legend when your engine does not perform. An example is where the throttle body has been opened to provide the additional air to the engine when the accelerator pedal is released. Without Rotational Idle, the engine would idle excessively high. To control the idle the Nexus VCU will cycle through cylinders to be cut to keep the engine below a set RPM amount. As RPM approaches this set amount more cylinders are cut.

Rotational Idle is not required for all Anti-Lag configurations, only those configurations where the additional air flow is not switchable.



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