When you visit a large motorsport trade show, as I recently did, there will be a number of engine component suppliers present, some of which will be selling high-quality valvetrain components. In the display cabinets ranged before you, among other things you are likely to see valves of all sizes, shapes and materials, there for you to examine and discuss with the various specialists manning the stands. Among these exhibits, there is sometimes a single, horribly distorted part, proudly...