From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Page discussing criticisms and proposed changes to spark control, carburation control, and shutter systems.
| Identifier | ExFiles\Box 154\3\ scan0074 | |
| Date | 25th March 1929 guessed | |
| - 2 - Spark Control. Since the spark is in practice on American cars never retarded for starting (the automatic centrifugal advance being relied on for this) in a lot of the cheaper cars there is no manual spark control at all. This omission of the spark control seems inadvisable at present, but much better methods of controlling the spark may soon be available (see OY2 February 9th.) in which case manual spark control could reasonably be omitted. Carburation Control. We should like to suggest that the carburation control be omitted from the steering column and combined with the control of the pilot jet by a single lever on the instrument board. We have such a proposal on the drawing board of which I would like to send a print shortly. Our proposal is that the handle on the instrument board should change the mixture from "normal" to "rich" in the first half of its stroke, and open the pilot jet in the second half. This would make it impossible to obtain a mixture leaner than normal, but from the point of view of the average driver who never uses the left hand side of the present quadrant, this would be no disadvantage. Our carburation lever on the column is inclined to give the new driver the impression that the car is difficult to drive and that there must be defects in the carburetter to make such a control necessary. Another criticism is that the control of mixture for starting the car is in two different places, partly on the column and partly on the instrument board. This causes confusion in the driver's mind, since he is generally used to handling conventional cars, and leads to bad starts due to improper handling. Shutter. A similar criticism applies to the hand operated shutter namely that it unduly complicates the handling of the car. Practically all cars now have automatic means of controlling temperature. All the better cars have automatic shutters. We have recently made tests of these on our own cars which show that they work much better than we had expected. By mounting the operating thermostat in the top tank of the radiator loss of alcohol when the car is standing is largely prevented. The water temperature can be held at 160°F under all weather and operating conditions without any variation of more than 5° either way. -continued- | ||