Line lock

Without brake input, drivers staging their vehicle at the starting line would roll if the clutch was slightly engaged.

[citation needed] The line lock prevents vehicles from rolling by allowing the driver to control the clutch and accelerator using foot input and braking with the hand.

[1] Although less common, rolling burnouts can be achieved with modified line locks by proportionally increasing the front brake pressure and the throttle to keep the car at a steady speed.

The only advantage for such a setup is the ability to maintain a burnout at relatively low wheel speeds, which reduces wear on the rear tires.

This method can be used to increase tire temperature to provide better traction prior to a drag run, but it is also often used purely for show, such as in drifting exhibitions or simply for the personal enjoyment of the driver.

[citation needed] Many modern sport-oriented cars now offer optional line locks for drag and show purposes, such as the so-called "burnout mode" found on the 2015 Ford Mustang.