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).
Revisions to throttle controls for a slower start opening on various car models including the Silver Phantom.
| Identifier | ExFiles\Box 109\1\ scan0165 | |
| Date | 1st September 1939 | |
| 666 BY/NS.{Norman Scott} c. Rm{William Robotham - Chief Engineer} c. Rm{William Robotham - Chief Engineer}/IMW{Ivan M. Waller - Head of Chateauroux} c. Rm{William Robotham - Chief Engineer}/FD.{Frank Dodd - Bodies} DA.{Bernard Day - Chassis Design}3/N.1.9.39. Silver Phantom - Throttle Controls with Slow-start Opening. ------------------------------- Please receive herewith: E.CD.1514 - Revised Throttle Controls -Slower Start Opening - Comet, Cresta, Silver Dawn 80, and Silver Phantom. The original designs for these controls to E.CD.1376/7 allowed for the same rate of throttle area opening as for Wraith III which is affected by the angular movement of the throttle from shut to fully open. The angular movement of the B.80 carburetter throttle is 87° whereas the Wraith III throttle only moves through 78° which gives a much faster initial throttle opening for the Wraith III per degree of throttle movement. As reported by Rm{William Robotham - Chief Engineer}/IMW{Ivan M. Waller - Head of Chateauroux}, the carburetter of the car 30.G.V11. was found to have a too sudden throttle opening causing the car to accelerate violently with a very small pedal movement, this was improved by altering the set-up of certain throttle control levers, the resulting throttle opening curve being shown on E.CD.1514 by dotted lines on the graph. The modifications called for on E.CD.1514 give a slightly slower opening still as shown by the full line on the graph and are obtained by the use of two new levers and one new pull rod with revised lever setting. Will you therefore please instruct these modifications to be made to the controls of chassis 30.G.V11. The alterations apply to all cars fitted with the B.80 engine as follows, Comet, Cresta, Silver Dawn 80 and Silver Phantom. DA.{Bernard Day - Chassis Design} | ||