Rallying Starting Timing Beam

[Littlefysh]

Hi All,

I'm wondering if anybody can help me, I'm trying to find a source to reference about at least one rallying series (preferably the WRC) using a laser beam to start their timing at the beginning of a stage? I seem to remember this was used, but I'm either remembering this wrong or I'm using the wrong words to Google it.
I also seem to remember reading/hearing somewhere years ago that the timer doesn't start when the countdown is zero, but as a result of the beam being there it starts when the car breaks the beam or something like.

Any help is appreciated, many thanks.