The 6 L auto was cheered by the Rolls-Royce Phantom I as a closed-body auto. Although founded on the three L, it corporate more improvements.

Like the four cylinder locomotive, Bentley's straight-6 included elevated camshaft, 4 valves per cylinder and two sparking plugs per cylinder, all foreign technologies at the term, as good as a single-piece locomotive stop and question form in iron, and thus no question gasket to gas.

Bore and shot dimensions were very to the 4½ L machine at 100 mm (3.9 in) and 140 mm (5.5 in), respectively, having a whole of 6.6 L (6597 cc/402 in³) of shift.

180-200 hp (134-149 kW) was produced, and the automobile was faster and more certain than the emotional Bentley Blower produced at the very second. Extended forms of wheelbases were produced for much a low-production machine, ranging from 132 in (3353 mm) to 152½ in (3873 mm.