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 from Lendrum & Hartman Limited discussing engine tappet adjustments and low-speed performance.
| Identifier | ExFiles\Box 124\3\ scan0315 | |
| Date | 18th February 1935 | |
| Messrs. Rolls-Royce Ltd. -2- 18.2.35. a reply as to whether or not the two Door Stops we have in stock will meet your requirements, at least for the moment. We are pleased to hear that the Buick is going quite well, and in reply to your suggestion in connection with tappet clearances, we fully appreciate this point, but, on the other hand, the procedure you have adopted in connection with adjustment of these tappets does definitely give a better idling and slow running speed. The official Manual, however, suggests that these engines should not be tuned below the equivalent of 8 m.p.h. top gear performance, and we here at Willesden adhere rigidly to the Factory specification in relation to tappet adjustment and no effort is made to tune the engines below the speed designated. It has been our experience here at Willesden that when the valves are adjusted as you suggest, you are doing in your letter, slow running is improved, but the balance of the performance is not as efficient as with the correct tappet setting. We would be pleased to hear whether or not this has been your experience. Awaiting your further instructions in connection with the despatch of these Door Stops and alternative type of Jack, we beg to remain, Yours faithfully, FOR LENDRUM & HARTMAN LIMITED, M.G.ARMSTRONG, Manager. | ||