Accurate and timely recording of data is essential for the operation of an engine testing laboratory. A computerized automatic data acquisition system is described in detail. It is pointed out that setting up specifications and modes of operation for a system such as this are best arrived at by mutual discussions between the purchaser and supplier after the purchaser has gained a basic understanding of the operation and limitations of the equipment he is going to buy. System functions, operations, hardware, software, measurement methods, etc., are described. Measurement problems with solutions to these problems, along with operational experiences, use factor, operator acceptance and training over a 1-1/2 year period are presented. A closed loop system for automatically controlling the speed of an engine is illustrated.