The final example of the Bentley 6.75 litre V8 engine has been produced this week, marking the end of a 61-year run for the L-Series engine which has seen a production run of 36,000 units over various iterations. This goes into the last of the 30-unit run of the Mulsanne 6.75 by Mulliner which was unveiled in January.

This L410 engine is laid back for a petrol-powered engine given its prodigious outputs, producing its 530 hp at 4,000 rpm and 1,100 Nm of torque from 1,700 rpm in the Muslanne 6.75 by Mulliner, or identical to the figures from the Mulsanne Speed. When the L-Series engine first arrived in 1959, it displaced a capacity of 6.25 litres in the Bentley S2, used carburettors and was naturally aspirated, producing around 180 hp.

The original 6.2 litre engine was redesigned to fit the Bentley T-Series in 1965, the engineers having reduced the engine’s overall dimensions to fit under a lower bonnet. Capacity grew to the six-and-three-quarters it has been known by since, retaining its bore measurements but gaining stroke to 3.9 inches (99.06 mm) for more torque.

The first Bentley to wear the Mulsanne name arrived in 1980, and regulations of the time required improvements to occupant safety and emissions, the former seeing the inclusion of a collapsible water pump and shortened the engine’s overall length by 10 cm. The Mulsanne Turbo that followed added a single turbocharger to the engine, making it the first forced induction Bentley since the ‘Blower’ models of the 1920s.

The single turbocharger was afterwards supplanted by a twin-turbo setup, and was joined by fuel injection as well as full electronic control. The ‘six-and-three-quarters’ engine underwent another major overhaul with the advent of the current-era Mulsanne in 2010, bringing a new crankshaft, new pistons, new connecting rods and new cylinder heads that enabled variable valve timing and cylinder deactivation.

The retirement of the L-Series 6.75 litre V8 engine leaves Bentley with the 6.0 litre biturbo W12, 4.0 litre biturbo V8 and 3.0 litre turbo V6 hybrid, the latter two engines also shared across the wider Volkswagen Group. Full electrification is on the cards for Crewe too, with studies such as the EXP 100 GT concept packing four electric motors and 1,500 Nm, for 0-100 km/h in 2.5 seconds and 300 km/h flat-out.

GALLERY: Bentley Mulsanne 6.75 Edition by Mulliner