W. O. increased the bore of his six-cylinder engine from 80 millimetres (3.1 in) to 100 millimetres (3.9 in). With a 140 mm (5.5 in) stroke, the engine had a displacement of 6.6 L (6,597 cc (402.6 cu in)). Like the four-cylinder engine, Bentley’s straight-6 included overhead camshaft, 4 valves per cylinder, and a single-piece engine block and cylinder head cast in iron, which eliminated the need for a head gasket. In base form, with a single Smiths 5-jet carburettor, twin ignition magnetos, and a compression ratio of 4.4:1, the Bentley 6½ Litre delivered 147 horsepower (110 kW) at 3500 revolutions per minute. You can find more visual details of the 1930 Bentley 6.5 Litre gallery by scrolling up.
The Bentley Speed Six chassis was introduced in 1928 as a more sporting version of the Bentley 6½ Litre. With a single-port block, two SU carburettors, a high-performance camshaft, and a compression ratio of 5.3:1, the Speed Six’s engine produced 180 hp (130 kW) at 3500 rpm. The Speed Six chassis was available to customers with wheelbases of 138 inches (3,505 mm), 140.5 inches (3,569 mm), and 152.5 inches (3,874 mm), with the 138 inch wheelbase being most popular.
You can find more visual details of the 1930 Bentley 6.5 Litre gallery by scrolling up.