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).
Record of a telephone conversation discussing design proposals for the Bensport engine's camshaft and appearance.
| Identifier | ExFiles\Box 3\4\ 04-page057 | |
| Date | 17th June 1932 | |
| K4653 E.{Mr Elliott - Chief Engineer} FROM R.{Sir Henry Royce} C. to SG.{Arthur F. Sidgreaves - MD} WCR. C. to RG.{Mr Rowledge} BY.{R.W. Bailey - Chief Engineer} HS.{Lord Ernest Hives - Chair} R1/M17.6.32. RECORD OF TELEPHONE CONVERSATION ON 17.6.32. re. BENSPORT ENGINE. I was in London yesterday with SG.{Arthur F. Sidgreaves - MD} and WCR. The most important part of our discussion concerned the Bensport engine, as SG.{Arthur F. Sidgreaves - MD} was not happy about it being the same as Peregrine, and accessories being similar. Strictly speaking it is the engine appearance that would make the difference, so the following proposals were settled. (1) The engine should have overhead camshaft or camshafts. If we thought the best arrangement was a double camshaft - which we were working on - we should go on with that design, but I am rather inclined to think that the double camshaft will be a double difficulty in keeping it from rattling, and that we should do better to settle down to a single camshaft design. Our aero engine design might be made to fill the book, with a different drive. You have a head with 6 inlet ports and 6 exhausts, which will give a good position for the sparking plugs, with valves of the maximum dia. we can get in the bore in a straight line along the head, the inlet branches which do not require watercooling occupy the other side of the engine, and in the arrangement that occurs to me to be worth thinking about the camshaft would be out of centre sufficiently we will say, to the R.H. side, to permit of the adjustment of the tappets, with rockers like on our aero engine. We should have one disadvantage, in lubricating the cams, and the oil flying about, but this would not be worse than on our aero engine, which is I understand quite good. It makes a very good mechanical arrangement, a little high in the head perhaps. In fact, it is a push rod head with an overhead camshaft applied to it, and single ended rockers. Try this over as one of the arrangements. The other would be to have the same camshaft and put it down under the rockers, for which we should have to provide a pivot (for the rockers) up level with the end of the valves, in fact, it would be bent pushrod rockers with the camshaft underneath. This scheme is not quite so good mechanically, being not so direct | ||