Specifications and Tolerances Students designing and building CO2 racecars experience the same challenge faced by many engineers: working with specifications and tolerances. * Specifications are a detailed set of requirements. Specifications can be measurements, capabilities, or limitations on a product’s size, weight, or functionality. Often a designer is handed a set of specifications before he or she begins a project. Product X must be able to do this, go this fast, and be roughly this size. The challenge for the designer is to be creative and develop an innovative, effective solution while working within the established parameters. * Tolerances are usually dictated to control the quality of a product. No two parts are ever made exactly the same. There are minute differences (perhaps a few ten-thousandths of an inch) in the measurements of two similar parts. Some variance in measurement is considered acceptable, as long as it’s not too great. A tolerance is an acceptable variance from the specified measurement.