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).
Page discussing engine ignition advance modifications and material testing, including a performance graph.
| Identifier | ExFiles\Box 65\1\ scan0195 | |
| Date | 23th April 1926 guessed | |
| contd :- -3- GRAPH I 1804 MADE AT CROXLEY Ignition Advance Flywheel ° ENGINE R.P.M. DELAYED LOW SPEED ADVANCE DUE TO GOVERNOR WTS BEING UNABLE TO LIFT SMALL INNER PISTON (OIL VISCOSITY ADDITIONAL WHEN STONE COLD) LIMIT OF ADVANCE FOR MAX POWER. 2°-3° INITIAL ADVANCE STANDARD AND T.E.X The reason we were unable to reduce the advance at high speeds was because the governor design did not allow us to fit control springs of the necessary rating. We have the strongest springs we can fit with a safe stress. The only alternative was to reduce the governor weights. We considered that this was undesirable because with the present weights the small inner piston does not commence to lift until 700 r.p.m. We have, however, been carrying out tests with reduced governor weights and a small inner piston of reduced weight. Previously we have not used aluminium for this item because it shewed a greater tendency to stick than brass in the presence of grit. We are now sending this item for a 10,000 miles test in duralumin. The relay that we contd:. | ||