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).
Engine bore wear, re-boring mileage, and the potential use of chrome plate inserts.
| Identifier | ExFiles\Box 132\5\ scan0115 | |
| Date | 16th March 1940 | |
| 1123 & 1124 To Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation} Rm.{William Robotham - Chief Engineer}2/MH.{M. Huckerby}16.3.40. We think it is very important that we should get a good picture of the average wear over the full length of bore from car engines run under different conditions. We say this because at the present moment we know that a number of our cars require re-boring at 25,000 miles. We also feel fairly certain that if we put a chrome plate insert in, these will run something better than 100,000 miles. However, on examining the figures obtained on various American cars, we see that the wear at the top lip is no more than twice the wear halfway down the bore. This suggests that we may have to put an insert in which is at least half the length of the bore. We cannot believe that the difference in cost between fitting a full length and a short insert can be very great. Rm.{William Robotham - Chief Engineer} | ||