Development of race engines has traditionally been a very hardware-intensive process. This is particularly true when trying to maximize the performance of a given engine. The engine developer must identify the inadequately designed components, and then attempt to optimally redesign them.Cylinder-pressure based combustion diagnostics can help identify the performance-limiting componentry, and can provide direction for the redesign of that componentry. However, effective analysis requires that exacting care be taken when instrumenting the engine, acquiring the data, and interpreting the results. This memo addresses each of these facets of the analysis, and discusses applications of cylinder-pressure based diagnostics such as structural loading, air-flow distribution, cycle-by-cycle and cylinder-by-cylinder torque variability, individual-cylinder losses due to non-optimum spark timing, selection of optimum fuel-injection timing, response to throttle transients, and quantification of burn rate.