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).
Bench tests comparing different contact point materials and ignition arrangements.
| Identifier | ExFiles\Box 35\6\ scan 216 | |
| Date | 24th December 1926 guessed | |
| -3- Contd. effect on the contact points as we have obtained with both U.S.A. and British tungsten fitted to the Delco-Remy contact breaker. We have also made the experiment (No.18) of platinum points on the Delco-Remy, with a result which in that case also is considerably better generally than the results obtained with the same platinum on our own contact breaker. The particulars of the actual bench tests, each of which has been the equivalent to 10,000 miles at an equivalent speed of nearly 30 m.p.h. are given on attached sheets. The first group of tests Nos.1, 4, 7, 10P, and 18 (green Nos.) have been on platinum. The second group, Nos. 2, 5, 8, 10T, 11 and 14 (blue Nos.) have been on tungsten points (whether British or U.S.A. does not affect the matter) on our own contact breaker. The third group, Nos.3, 6, and 12 (red Nos.) have been on the Delco-Remy contact breaker. The ignition arrangements under which the various Nos. were run were as follows :- Nos.1, 2, 3, 10P, 10T, 11, 12 and 18 were run with the previous standard ignition arrangement of coil (coarse primary) (finer primary is now standard), ballast resistance and RR. condenser. (Where the Delco-Remy unit was used it was only the contact breaker and the distributor which was utilised). Nos. 4, 5 and 6 were run with the new standard type GP. finer primary coil, standard ballast, and standard RR. Condenser. Contd. | ||