Show/Hide Toolbars

MaxxECU online help

Navigation: Settings > Motorsport

Power management (former After launch power limit (ALPL))

Scroll Prev Top Next More

MTune 1.108 testversion

 

Merged with the older After launch power limit (ALPL), check your settings really carefully after update!

 

Functionality to reduce engine power (and optimizer starts in drag racing applications) after launch control and ramp power back during a specific time-period.

Note: This functions requires the launch control function to be used.

 

Switch activation can be triggered by one of these three methods: Digital inputInternal outputs or Virtual input.

 

Required sensors

The system is based on the "Driven wheelspeed" value. This can be from rear wheel sensors or from a driveshaft speed sensor.

The input need to be setup in update rate = High speed mode. With little to no filters active, see driveshaft speed sensor.

The sensor can have any number of teeth, but more teeth give better performance.

For sensors mounted to the wheels: 32 or more teeth.

For drive shaft mounted sensors: 8 or more teeth.

It's important that the trigger wheels and sensor mounts are precision machined, as any deviation in the pattern or sensor vibration can cause the speed value to fluctuate.

 

 

Power management

 

Enable

Disabled

Enabled, always on

Enabled, by digital input - Uses the Power management system enable digital input.

 

Timer start mode

Selects how the "Time after launch" timer is started.

Launch control input release - Uses the launch control switch, enable stage x digital input.

Clutch switch input release - Uses the clutch switch digital input.

Transbrake input release - Uses the transbrake hold digital input.

 

 

Power management settings

 

time after launch power limit

This is a time based retard and cut system that can be used with or without speed sensors (active power management).

Uses predetermined ignition retard and engine cut values based on the time after launch. Used to optimize the traction right after the launch.

 

 

Speed based active power management

Uses a target speed table to restrict the engine by ignition retard and fuel/ignition cut to reach a predetermined acceleration curve.

 

Cut method

Specifies power cut method

Ignition - Drop ignition and/or retard ignition timing advance from the below tables.

Fuel - Drop fuel to reduce engine power. <-- use with caution.

 

Disable above gear

Used to disable the system over a set gear. Used with manual transmission where the system can't be used above a certain gear.

 

Disable above speed

Used to disable the system over a set speed. Used with manual transmission where the system can't be used above a certain speed.

 

 

Time after launch power limit

 

Ignition retard

Specifies ignition retard vs time after launch.

Note: The last (most right) cell MUST be 0 degree.

 

Spark/fuel drop

Power limit with "event drop" vs time after launch. 100% = shut off.

Note: The last (most right) cell MUST be 0 degree.

 

 

Speed based active power management

 

Target speed

Uses a target speed table to restrict the engine by ignition retard and fuel/ignition cut to reach a predetermined acceleration curve. Import of data from a logfile is possible as a starting point, see below examples.

Note: The tune selector is always "1" in MTune 1.108, that features is not yet implemented into the system.

 

Cut table

The engine cut and retard is determined by the deviation from the target speed.

The retard can be negative (ie. adding timing). But the timing overall timing adjustment from both the active power management and after launch limiter cannot advance the timing, only retard it.

 

Retard table

The engine cut and retard is determined by the deviation from the target speed.

The retard can be negative (ie. adding timing). But the timing overall timing adjustment from both the active power management and after launch limiter cannot advance the timing, only retard it.

 

 

Examples

 

Import a baseline

clip0427

Open a logfile, select the area with SHIFT-key and left mouse_press, the right click and select Selection --> import as baseline for Power Management, after the baseline has been imported, everything can be tuned from there.