The V8's famous burble comes from lopsided firing in each cylinder bank
That deep, rumbling V8 soundtrack is a side effect of geometry. In a typical road-car V8, the cylinders fire in an order that jumps unevenly between the two banks, so each bank's exhaust pulses arrive at irregular intervals. Pipe the banks separately and the uneven beat becomes a burble. Racing engineers, chasing power, work hard to get rid of it.
The culprit is the cross-plane crankshaft used in most road V8s. Seen end-on, its four crankpins form a cross, set at quarter-turn intervals. That layout gives excellent balance and low vibration, but the firing sequence it demands leaves each bank breathing unevenly. Sixties racing cars such as the Ford GT40 used long tangled exhaust pipes to even out the pulses.
The alternative is a flat-plane crank, with all pins in one plane. It is lighter, needs no counterweights and lets exhaust pulses alternate neatly, which suits racing; the Cosworth DFV used one to dominate Formula One from 1967, and Ferrari's road-going V8s have long followed suit. The trade-off is more vibration. Early V8 cars, including a 1915 Cadillac, used flat cranks simply because they were easier to make. Most V8s set the banks 90 degrees apart for balance, accepting a wider engine.
The layout arrived in 1904 with the French Antoinette engine, designed by Léon Levavasseur for speedboats, cars and later aircraft. In 1907 a Curtiss V8 motorcycle hit an unofficial 219 kilometres an hour. Rolls-Royce put a V8 in a road car in 1905 but built only three before going back to sixes, and Edward Hewitt praised the design's light weight and compactness when he fitted one to an American touring car in 1907.
Mass popularity followed. Cadillac's 1914 V8 sold 13,000 in its first year, helped by the company's early electric starter motors, and Ford's Flathead V8 of 1932 made the engine a fixture of everyday motoring.
Source: V8 engine
