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).
Chevrolet specifications and observations on Aero Battery Ignition systems.
| Identifier | ExFiles\Box 163\7\ img299 | |
| Date | 13th November 1936 | |
| -2- Rm{William Robotham - Chief Engineer}/Wst.11/AP.13.11.36. The Chevrolet specification is as follows:- Model 645.T. and 680.L. Vacuum control Auto starts at 600 engine r.p.m. 28° on flywheel at 3000 r.p.m. 16 - 18° Vacuum control commences with 5" Hg. maximum with 9" to 11" Hg. They do not favour an "Octane Selector" as it is liable to be misused and they have had service complaints of "pinking" due to this cause. 3. Aero Battery Ignition They are going in for this wholeheartedly. I saw drawings of a complete 14 cylinder distributor unit for Armstrong Siddeley very similar to our own 12 cylinder unit. The design of the generator is causing them some concern and the one Kennington shewed me was about half again as large as ours and was only generating 6 volts, at a speed higher than our generator requires to generate 12 volts. Single cylinder units were in process of manufacture for Messrs Bristol and several complete engine sets have also been supplied to Pobjoy. Rm{William Robotham - Chief Engineer}/Wst. | ||