For some time past I have owned a 1926 3-litre Bentley which has been fitted with a Ford diesel unit of 3,600 c.c. This combination is sometimes frowned upon by people ready to condemn without reflecting on the common-sense advantages.
Externally the car is a very fine example of the Gurney-Nutting long-chassis “Blue Label”, original down to the complete set of 3-litre instruments. The Bentley engine met with an accident, and as a replacement would have been extremely difficult to locate, the diesel was the obvious answer. The engines have much in common in that they are both large, powerful, four-cylinder engines turning over fairly slowly.
The benefits of the diesel are not always appreciated by the ordinary motorist. The essential point is that the compression-ratio is 16 to 1 and is responsible for ignition. That does away with sparking plugs and carburetter. Performance does not equal that of a petrol engine; acceleration is unimpressive from standstill, but improves at 35 m.p.h. to give useful urge in top gear up to 60 + m.p.h. Fuel consumption at 38 m.p.g. on the open road and 28 m.p.g. in London jams is kind to the pocket and is ample compensation for lack of dash. The 3-in. exhaust. has a note very little removed front the real thing and the alarming diesel knock, which provides plenty of amusement at low revs, disappears when cruising at 50-60 m.p.h.
I hope the points mentioned in this letter will make readers think twice before they look down on the diesel-engined car, and give the diesel engine itself the credit it so richly deserves. I am, Yours, etc., Kenneth J. Sheppard.