A V8 engine has two rows of four cylinders arranged in a V shape, and – in the cross-plane crankshaft type, rather than a flat-plane – these cylinders fire in an irregular pattern across the two rows.
During each piston’s cycle it produces a pulse of air pressure, which is forced out through the exhausts (they effectively become wind instruments). Each pulse makes a tone, which combined with the other pulses forms a harmonic series. The same thing happens in all engines, but it’s the irregular firing sequence that gives a big V8 its distinctive throbbing sound.
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.
