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).
Test report on a finer primary coil for the Phantom test bed engine.
| Identifier | WestWitteringFiles\Q\December1926-January1927\ 91 | |
| Date | 7th January 1927 | |
| EFC. WB.{Mr Brazier/Mr Bell}123. 7.1.27. TESTS OF FINER PRIMARY COIL ON PHANTOM TEST BED ENGINE. We have now completed tests on the engine with finer primary coil No. CF6. in accordance with suggestions contained in Re/MLS.9.26. The first test consisted of running the engine with battery ignition only at the maximum permissible speed, which in this case was 2750 r.p.m., with a battery voltage of 10 volts. (This engine speed corresponds to a road speed of 79 miles per hr). The carburetter mixture control was kept normal to avoid any misfiring due to carburation, and the ignition lever was kept as far retarded as possible whilst the brake torque was kept at a maximum. The engine was maintained at this speed for 5 mins. and no misfiring occurred. The temperature of the coil case during this test was estimated at about 50°C. The volts were then reduced to 8 and the maximum regular firing speed of the engine ascertained. This was found to be in the neighbourhood of 1000 r.p.m.; above this speed occasional misfiring occurred which developed worse as the engine was speeded up. N.B. The reason why 3000 r.p.m. was not reached was because the engine was rather old and bad crankshaft vibrations occurred at speeds in excess of 2750 r.p.m. EFC/H.E.West. | ||