How to Get a Good Reaction Time

Reaction time is the first number on the timeslip, the results screen that pops up when a race ends. It is how quickly the car actually left after the Christmas Tree went green. The launch itself is covered in How to Race. This page is about reading the number and getting a legal light.

What the number means

• A small positive number, such as 0.050, is a legal light. Lower is better, as long as it stays at zero or above.
• A negative number is a red light. You left too early. The total on the timeslip is blank, so the quicker car still loses that run.

A late light still counts, but it adds time. Do not wait until green is fully on. The car sits for a split second before it moves, so a good light is lifting as the last yellow is disappearing. Lift too early and you get a red light, and that run is thrown out.

How to get a good light

1. At the start, hold the pedal and bring the tachometer on the left into the green zone. Move your finger side to side until the arrow in front of the car is straight and green.
2. Watch the Christmas Tree. The lights go from yellow to green.
3. Lift as the last yellow is disappearing. Do not wait until green is fully on. The car sits for a split second before it moves, so that early lift is how the number gets small. Lift too early and RT goes negative: that is a red light and you lose.
4. After the race, read the reaction time on the timeslip before you look at anything else.
5. If it is negative, wait a hair longer next time. Do not wait until green is fully on.
6. If it is legal but large, start lifting a little earlier on the next run. Stay at or above 0.000.

The car still has to cover the track. A perfect light plus a slow car can lose to a later light and a quicker car. That tradeoff is in Why a Faster Car Matters.