Abstract: An internal combustion engine performance analyzing system is described for displaying a number of operating characteristics, such as engine ignition and cylinder power, which exists under selectively controlled operating conditions. Simple connections to the engine provide the necessary signals to the solid-state electronic analyzer. Various pattern display modes may be selected. An anticipatory cylinder fire signal, which is related to crankshaft rotational degrees, permits a given cylinder to be shorted for the desired interval, regardless of the engine speed. This anticipatory cylinder fire signal is obtained from a servoed ramp waveform generator. Individual cylinder waveform patterns are synchronously and simultaneously displayed on an oscilloscope.