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).
Ignition timing issues, detonation, and other suggested modifications for the Phantom 10-EX experimental car.
| Identifier | WestWitteringFiles\P\July1926-September1926\ Scan118 | |
| Date | 23th September 1926 | |
| TO HS.{Lord Ernest Hives - Chair} FROM R.{Sir Henry Royce} Copy to BJ. ORIGINAL re. PHANTOMS. (10-EX.) X8774 XP680 I find it very difficult to get ignition starts regularly from 10-EX. Naturally the engine does not stop in the same position every time, and the control does not carry it far enough in either one or the other direction according to the timing of the battery ignition (even when carefully returned to best position for ignition starts.) On 10-EX. I found the magneto very late and the battery ignition very early. After several tries I managed to time them equally, with a great improvement in the engine as regards detonations. During the experimenting with this I found the battery ignition cam sticking very badly on its spindle. It suggests a quicker taper - see another memo. I do not know if on this engine the ignition advance has the improved characteristics: if not, it would materially reduce the tendency to detonate and naturally permit of increase in the compression ratio, which would not be detrimental. When 10-EX. is next in Derby it would be as well to remove the pressure cooling: the extra gauge detracts from the appearance. The gearbox on this car wants drilling to relieve the oil pressure in the position plungers. X1357 It would be a good car on which to fit the Zeiss headlamps. Regarding protection from the weather it is absolutely necessary on any high speed car to have face protection for the back passengers. The huge heavy screens sent on a previous occasion do not appear to be very suitable: surely there is something better known. I should suggest a permanent windscreen right across the car, but not very high, with folding side pieces, but there must be something standard. 8 60 27 Sep 1926 R.{Sir Henry Royce} | ||