Music from Modena: The Melodic Ferrari V8

by James Kraus

JK - 1 (6)

Jean-Claude Andruet and Michèle “Biche” Espinosi-Petit on their way to overall victory at the 1982 Tour de France in a Ferrari 308 GTB

Why do Ferrari’s V8’s sound so delicious, almost as enticing and melodious as a V12? It comes from the use of a single-plane “flat” crankshaft in lieu of the typical cross-plane (two-plane) crankshaft. Workaday V8 engines utilize the cross-plane crank to optimize mechanical smoothness; an admittedly important consideration when transporting a hedge fund manager and his mistress to a performance of Die Walküre at the Théâtre de Genève in a BMW 750i, or a load of sensitive electronic test equipment behind a MAN TGX in route to the CERN Large Hadron Collider.

MAN TGX V8 Diesel

While a twin-plane crankshaft design is mechanically smoother, more power can be squeezed from a single-plane configuration. The power advantage stems from the firing order.

In a cross-plane configuration, the firing order results in sequential cylinder-firing occurring on both common and opposing banks. This results in exhaust pulses in each bank that are uneven, with large time gaps when two cylinders fire sequentially on the opposite bank. The unevenly spaced pulses make high rpm exhaust scavenging less effective and result (when lightly muffled) in the flatulent, staccato motorboat sound so beloved by muscle car, truck and Harley-Davidson enthusiasts.

In the flat crank design, used by all F1 teams and every Ferrari V8 road car ever constructed, sequentially-firing cylinders are always on opposing banks. This results in a even spacing of exhaust pulses within each bank of cylinders, allowing for very efficient scavenging of exhaust gas at high revs. Not surprisingly, it also emits a much smoother, more melodious soundtrack, rising from a smooth well-tempered rumble to an otherworldly fortissimo crescendo as it climbs toward the redline. Think of it as Luciano Pavarotti as compared to Ozzy Osbourne.

Good sounds radiate from Modena: The Northern Italian comune, home of Ferrari headquarters, was the birthplace of both Enzo Ferrari and Luciano Pavarotti.

Heavy Metal: A cross-plane crankshaft produces the gruff tones and staccato dissonance reminiscent of an Ozzfest

BMW took a novel approach to the exhaust-pulse timing issue when they designed their twin-turbo S63 V8 (currently used in the X5M and X6M.) They retained their traditional two-plane crankshaft, but they turned the cylinder heads inside-out so that the exhaust ports empty into the vee between the cylinder banks, and the intake ports face outwards.

By then placing the turbochargers into the vee and adopting clever manifolding, they made it possible to feed each turbo with sequentially-firing cylinders from either bank. In this way, each turbo impeller is accelerated by a smooth, uninterrupted flow of exhaust gas, drastically lowering spool-up time, and providing near instantaneous throttle response.

The S63 sounds similar to a V8 Ferrari except for the fact that the spinning turbine wheels muddy the exhaust note a bit, slightly masking the inherent sound signature.

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4 thoughts on “Music from Modena: The Melodic Ferrari V8

  1. Ferrari S.p.A. are protective of their unique sound as well. The Maserati and Alfa 8C versions of the Ferrari V8 have cross-plane cracks – Ferrari keep the flat-plane crank for themselves.

  2. It is quite possible that Enzo himself decreed that Ferrari retain the flat-plane crank for road-going versions of the V8.

    The Commendatore always had an ear for a good exhaust note and a key reason for his directing Gioacchino Columbo to develop the first 12-cylinder Ferrari engine was because he “always liked the song of twelve cylinders.”

    • No, I was indeed referring to a BMW.

      The current S63 Mercedes is powered by a conventionally-breathing V8 with outboard turbos that are fed exhaust pulses only from their respective banks. I realize the source of possible confusion: S63 is a model designation at Daimler; at BMW it is an engine code. The BMW S63 motor powers the X5M and X6M; I have revised the above text accordingly to emphasize the fact that I am describing an engine from Munich as opposed to Stuttgart.

      The new M5 V8 (the S63Tü) also utilizes BMW’s proprietary cross-fed turbochargers and reverse-flow cylinder heads.

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