Today’s internal combustion engines are continuously becoming more advanced and producing better horsepower-per-liter ratios. All of this advancement is occurring thanks to the use of a component that Edmond Berger invented in 1839: the spark plug. The spark plug takes an electrical current and forces it to jump a small gap, creating a spark that lasts only milliseconds. This gap is often a deciding factor in whether the car runs well or not at all.
Automakers build their cars to use spark plugs with gaps measured in thousandths of an inch. The gap on most mass-produced spark plugs ranges from 0.035 and 0.049 inches, with a tolerance of plus or minus 0.003 inches.