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.
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