Bentley's new Blower engine comes to life in Crewe

The engine for the first car in Bentley Mulliner's Blower Continuation Series has been fired up for the first time on a dedicated and specially-prepared testbed at Bentley's Crewe factory.

The Blower Continuation Series is a run of 12 newly-built recreations of one of the most famous Bentleys of all time - the supercharged 4.5-litre 'Blower' created for racing by Sir Tim Birkin in the late 1920s. Forming the world's first pre-war continuation series, these 12 cars have all been pre-sold to Bentley collectors and enthusiasts around the world.

The newly created Blower engines are exact recreations of the engines that powered Tim Birkin's four Team Blowers that raced in the late 1920s - including the use of magnesium for the crankcase.

The Blower engine started life as the naturally aspirated 4.5-litre engine, designed by W.O. Bentley himself. Like Bentley's 3.0-litre before it, the 4.5-litre brought together the latest individual engine technologies of the time - a single overhead camshaft, twin-spark ignition, four valves per cylinder and, of course, Bentley's now legendary aluminium pistons.

The racing version of W.O.'s 4.5-litre engine developed approximately 130bhp, but Bentley Boy Sir Tim Birkin wanted more. W.O.'s focus was always on reliability and refinement ahead of absolute power, so his solution to finding more power was always to increase engine capacity. Birkin had a different plan - he wanted to supercharge the engine, an idea that W.O. thought 'corrupted' his design.

With funding from his wealthy financier Dorothy Paget, and the technical skills of Clive Gallop, Birkin commissioned supercharger specialist Amherst Villiers to create a supercharger for the 4.5-litre. The Roots-type supercharger - colloquially known as a blower - was fitted ahead of the engine and radiator and driven directly from the crankshaft.

Internal modifications to the engine included a new, stronger crankshaft, reinforced connecting rods, and a modified oil system.

In racing tune, Birkin's new supercharged 4.5-litre engine was mighty - outputting around 240bhp. The 'Blower Bentleys' were therefore extremely fast - but as W.O. predicted, also somewhat fragile. The Blowers played their part in Bentley history, including helping to secure victory for a naturally-aspirated Bentley Speed Six at Le Mans in 1930, but over the 12 races that the Blowers contested, a victory was never secured.