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The torsional measurement capabilities of both an angular accelerometer and a toothed wheel - magnetic pickup were compared against the requirements for measuring generator set torsional motions accurately enough for an analytical model to predict operating shaft torques within ten percent. Three generator sets were evaluated, ranging in size from 4KW to 1250KW. If properly applied, both torsional measurement systems offered sufficient measurement accuracy. However, the angular accelerometer was preferred over the toothed wheel, since, unbeknownst to the user, the toothed wheel's signal could be significantly altered by the engine's linear shaking.

A valve train design procedure was developed which made valve spring design an integral part of cam profile design. This design procedure also incorporated the dynamic behavior of the valve train, by using a 21 degree of freedom computer model. The design goal was to maximize the area under the cam profile, limited by several design constraints, such as maximum cam-tappet velocity. The cam profile was free to take nearly any form, since it was composed of eight Bezier curves. This extremely complex design problem was handled via commercially available optimization software.

A computer model was developed to study the dynamic behavior of a pushrod/hydraulic tappet configured valve train. For accurate simulation, the model had 21 degrees of freedom, nine of which were used to model the valve spring. The model's damping values, and the stiffness of the hydraulic tappet, were empirically derived by correlating the model with experimental data. To achieve excellent correlation, two of the model's dampers had to be non-linear. This study did not include the impact of cylinder pressure. The computer model was used to study component loads and stresses over a broad engine speed range. The valve train was found to behave as a linear mechanical system with two significant modes of vibration. The harmful consequences of strongly exciting these resonant modes is covered, as well as ways to minimise these resonant responses.

Conversion of an air-cooled gasoline engine to propane fuel can result in an engine with lower exhaust emissions, longer life, and less maintenance. The role of the carburetion system in mixing, the development of a novel liquid withdrawal system, and the importance of engine temperature were vital to this successful conversion.