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).
Performance and hardness of a 6-cylinder distributor cam, comparing Delco, Lucas, and in-house models.
| Identifier | ExFiles\Box 168\3\ img235 | |
| Date | 24th April 1928 | |
| FRH. CHILDS "Can you give me an average for 6 distributor by Delco?" The position of the R-R cam is as follows:- "The contact points must break every 60 degrees during rotation of the cam with a tolerance limit of plus or minus one degree: overall error not to exceed two degrees. (this is doubled on the engine). Taking average figures during the last year we would say that the R.R. cam is the most accurate with only 1° to the above. The Lucas is slightly better than the Delco. This is to be expected as we pay more attention to finish and Brinell hardness. From the other firms, we obtain a brinell hardness of 500 whereas Lucas and Delco are not much above 400. Until recently the Delco were anything from 130 - 400. We find that a figure of 400 is sufficient. It is interesting to note | ||