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).
Letter to The Light Production Co. Ltd. discussing modifications to C.140 pistons for experimental runs.
| Identifier | ExFiles\Box 87\2\ scan0032 | |
| Date | 28th March 1935 | |
| 4236 Exptl. Dept. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}7/KW. 28th March, 1935. C.H.Brooks Esq., The Light Production Co.Ltd., 60/66, Rochester Row, Westminster, S.W.1. Dear Brooks, Thank you for your letter of the 26th March. The piston of 3¼" bore which has your Code No. C.140 would appear to be exactly what we want for our original experimental run. As there will be no question of endurance we should propose to machine .040" off the crown in order to reduce the compression height to what we require. Alternatively, if this would in your opinion make the piston too weak, we shall fit .750" gudgeon pins in the .875" holes, bush the holes and drill the gudgeon pin .040" out of centre. If you will let us have your opinion and an outline drawing of the piston, we could decide how we would tackle that and get the necessary parts made, but in any case we should like 14 C.140 pistons from you at the earliest possible moment, to the dimensions that you mention. You will of course grind these to our existing Bentley cam form. I was at Rovers yesterday and I asked Wilks to try a set of your pistons, which I think he will do. He is at the present moment using the Invar Strut type. Have you any direct comparison between the Invar Strut type and the Aerolite piston from the work you have done with Humbers ? If you have I should be interested in these figures. Yours faithfully, FOR ROLLS-ROYCE LIMITED. | ||