Valve timing of engines having intake pressures higher than exhaust
A 1932 NASA technical report, drawn from the NASA Technical Reports Server collection, on valve timing for engines whose intake pressure exceeds exhaust pressure, written for engine researchers and aeronautical engineers. Its pictures are plain line graphs with labelled axes and families of curves, each family set against degrees of valve overlap or manifold pressure, showing how performance rises and falls with changing conditions. A designer could take from them the restrained chart language of mid-century engineering: stacked parallel curves, bracketed labels down the right margin, and clean grid-ruled plots.
