Thermostatically operated choke for the Wraith model, including testing results and cost comparisons.
| Identifier | ExFiles\Box 7\4\ X 608 Carburetter-page54 | |
| Date | 11th January 1939 | |
| -4- THERMOSTATICALLY OPERATED CHOKE - WRAITH. The automatic choke control to Rm. {William Robotham - Chief Engineer} 579 has been running on 28.G.VI for about 5,000 miles without complaint. This includes a period of about one month when the car was loaned to Mr. Approximate costs. Bentley Startex. S.U. | Automatic Choke - Wraith. | Standard Wraith. --- | --- | --- Starter carburetter. i.e. increase in cost of S.U. carb. when fitted with startex - 7/6d. Thermostat switch - 2/6d. | Smith's Thermostat unit is a special one made for the job. A thermostat suitable to be fitted in the induction pipe would cost 7/6 to 10/-. | As a first approximation assume the deleted dash control to counterbalance the additional controls on the automatic system. As a first approximation assume boss on induction pipe and pipe from startex to centre of induction pipe to counterbalance controls deleted from standard set up. | The carburetter used was not standard, and it would have to be decided what class of finish would be acceptable before a price could be obtained. | The cost of fitting a thermostat in the cylinder head of the wraith to supplement that already operating the radiator shutters would be approximately 10/-. Rm {William Robotham - Chief Engineer} /T.A.Swinden. | ||
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).