A dial-in time is a term used in drag racing

Drag racing

Drag racing is a competition in which specially prepared automobiles or motorcycles compete two at a time to be the first to cross a set finish line, from a standing start, in a straight line, over a measured distance, most commonly a ¼-mile straight track....

 to claim how fast a racer's car is. Dial-in times function to determine which cars race against each other. If one car's dial-in time is significantly slower than another's, the slower car is given a handicap (which is done in E.T. bracket racing

E.T. bracket race

Bracket racing is a form of drag racing that allows for a handicap between predicted elapsed time of the two cars over a standard distance, usually 1/4 mile or 1/8 mile .-Goal:...

). The purpose of dial-in times is to make the race fair - so if a racer beats his or her dial-in time, he or she is automatically disqualified. Dial-in times can, however, be manipulated to be significantly slower than the car actually performs, in a technique called sandbagging

Sandbagging (drag racing)

Sandbagging describes someone who underperforms in an event. The term has multiple uses, such as a driver who competes in an event in a series below their level of expertise to finish high. In bracket drag racing and short track racing when a racer has a dial-in time / qualifying speed much slower...

.

Example

A car that runs 14.28, 14.30, and 14.32 seconds in quarter-mile practice runs could have a dial-in time of about 14.30 seconds. If the racer sets the time too low at 14.28, there is no guarantee that the car will actually run that fast in the real race, and time will be lost in the handicap to the opponent. If the racer sets his or her dial-in time too high at 14.32, there is a good chance the car will outperform that time and he or she will be disqualified.