A button activated launch control mode allows the driver to hold the engine with
a user definable, temporary lower rev limit with ignition retards, ignition cuts,
or a combination of both.
Turbocharged engines gain from increased launch boost with decreased launch engine speed; same power, lower engine speed. The further the throttle is pressed, the greater the boost, but with no increase in engine speed.
Normally asirated engines with very light flywheels can be launched consistantly at lower engine speeds with no engine 'bog down'.