Track Services Incorporated

TSI 2000+ Timing System

A Brief Explanation

Andy Marrs / Steve Horn

The 'TSI 2000+' (Track Services Incorporated) timing system is a P.C. based system designed specifically for drag racing. The computer hardware receives signals from the various sensors positioned at specific points on the track, the P.C. software then analyses the input data and outputs the required information to various sources; timing official, scoreboards, printers, etc. A single operator positioned in the timing control area at the track conducts the race control.

The start line infrared sensor set up consists of two dual emitter units and two dual receiver units. The emitter units are positioned to the outside of the track with the receiver units positioned in the centre of the track. In addition to these there are the guard emitter and receiver units.

Emitter units in position, guard emitter also shown.

Receiver units in position.

As the vehicle (car or bike) breaks the first beam it is deemed to be in 'pre-stage', this tells the driver/rider they are almost in 'stage'. When the vehicle breaks the second beam it is in 'stage', this tells the driver/rider the vehicle is at the start line. When the start sequence is operated, timing commences from the instant the stage beam is re-made (when the vehicle leaves stage). The guard beam is positioned to detect any breach of the roll-out rules, if the guard beam is broken before the stage beam is re-made it is a deemed to be a foul start. The timing data is then processed by the computer software upon receiving signals from the sensors positioned at various points along the track; 60 feet, 330 feet, 1/8th mile, 1000 feet and of course 1/4 mile. At each point, mounted on the outside of the track wall, is an infrared retroreflective cell. This emits a beam through a hole in the wall, which is returned via a reflector mounted in a foam block in the centre of the track. The vehicle breaks the beam as it passes the sensor and a signal is sent to the computer. Speed is measured by the use of an additional cell mounted 66 feet before the 1/8th and 1/4-mile sensors, creating a 'speed trap'.

Typical cell mount assembly.

Foam block and reflector.

Note hole in track wall.

In addition to controlling all the track sensors, the computer software is used perform all the standard race control functions, these include qualification positions, elimination ladders, and dial-in functions associated with bracket or handicap racing.

For further information please contact:


TSI Timers (European Division)

Steve Horn +44 (0) 1933 358245 email :

Andy Marrs +44 (0) 7747 616236 email :


TSI Timers (U.S.A.)

Tom Haggin / Paul Duke

SALES / SERVICE: 859-887-3290 / 3291

FAX: 859-887-3292

email :