Bentley re-creates digital model of the Birkin Blower

Bentley's Blower Continuation Series project has this week reached an important milestone, with the completion of the digital Computer Aided Design (CAD) model that will serve as the master design and engineering reference for the new cars.

Announced last year, the Blower Continuation Series is a run of 12 new Bentley Blowers, each of which will be an exact mechanical copy of the 1929 Team Blower built and raced by Sir Tim Birkin, and now likely the most valuable Bentley in the world.

The Continuation cars are being produced by a dedicated team in Bentley Mulliner's Classic division who cut their teeth on the recently restored 1939 Bentley Corniche, and who are now working with a team of vintage specialists to re-engineer and build the suite of parts needed to bring the new series of cars to life.

All 12 of the new cars are already sold to keen collectors around the world, and the first stages of build for Bentley's own engineering prototype, Car Zero, will begin in earnest soon.

Bentley's Team Blower has been carefully dismantled and then re-created in the digital world through a combination of precision laser-scanning and intricate hand measurement. The finished CAD model is comprised of 630 components across 70 assemblies, and is more than 2GB in size.

From start to finish, it has taken 1,200 man-hours for two dedicated CAD engineers to complete the model from the scan data and measurements, and the result is that an accurate and complete digital model for a 1920s Bentley now exists for the very first time.

The engineers have been able to complete the model while working remotely during the COVID-19 crisis.

Apart from the process of assisting the development of parts design and development, the CAD model has also been able to assist with the specification of individual customers' cars, with Bentley's Design team able to create accurate full-colour renders from the data. While the Continuation Series cars will be mechanically identical to the Team Blower, customers are now in the process of choosing their own exterior and interior colours palettes and materials so that the cars are visually distinctive from their predecessor.

Only four original 'Team Blowers' were built for racing by Birkin in the late 1920s. All were campaigned on the racetracks of Europe with the most famous car, Birkin's own Team Car No. 2, registration UU 5872, racing at Le Mans and playing a pivotal role in the factory Bentley Speed Six victory in 1930.

It is this car, now Bentley's own Team Blower, chassis number HB 3403, that is the master example for the Continuation Series.

As continuations of the original Team Blower, each of the new Continuation Series cars will feature four-cylinder, 16-valve engines with an aluminium crankcase with cast iron cylinder liners and a non-detachable cast-iron cylinder head. The supercharger will be an exact replica of the Amherst Villiers Mk IV roots-type supercharger, helping the 4,398cc engine to develop 240bhp at 4,200rpm. The car's structure will be a pressed steel frame, with half-elliptic leaf spring suspension with copies of Bentley & Draper dampers. Recreations of Bentley-Perrot 40cm mechanical drum brakes and worm and sector steering complete the chassis.