The R Type is the second series of post-war Bentley automobiles, replacing the Mark VI. Essentially a larger-boot version of the Mk VI, the R type is regarded by some as a stop-gap before the introduction of the S series cars in 1955. As with its predecessor, a standard body was available as well as coachbuilt versions by firms including H. J. Mulliner & Co., Park Ward, Harold Radford, Freestone and Webb and others.
Other than the radiator grilles and the carburation there was little difference between the standard Bentley R Type and the Rolls-Royce Silver Dawn. The R Type was the more popular marque, with some 2,500 units manufactured during its run to the Silver Dawn's 760.
Design
During development it was referred to as the Bentley Mark VII. Indeed the chassis cards for these cars describe them as Bentley 7. The R Type name which is now usually applied stems from chassis series RT. The front of the saloon model was identical to the Mark VI, but the boot (trunk) was almost doubled in capacity and the engine increased in displacement from 4.25 to 4.5 litres (as fitted to the later Mark VI). For buyers looking for a more distinctive car, a decreasing percentage had custom coachwork available from the dwindling number of UK coachbuilders. These ranged from the grand flowing lines of Freestone and Webb's conservative, almost prewar shapes, to the practical conversions of Harold Radford which including a clamshell style tailgate and folding rear seats.
All R Type models use an iron-block/aluminium-head straight-6 engine fed by twin SU Type H6 carburettors. The basic engine displaced 4.6 L (4566 cc/278 in³) with a 92.08 mm (3.6 in) bore and 114.3 mm (4.5 in) stroke. A 4-speed manual transmission was standard with a 4-speed automatic option becoming standard on later cars.
The early R Type Continental has essentially the same engine as the standard R Type, but with modified carburation, induction and exhaust manifolds along with higher gear ratios. After July 1954 the car was fitted with an engine, having now a larger bore of 94.62 mm (3.7 in) with a total displacement of 4.9 L (4887 cc/298 in³). The compression ratio was raised to 7.25:1.