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).
Thermostat temperature settings, carburation imperfections, and twin carburetors for 25HP and 45HP cars.
| Identifier | ExFiles\Box 5\4\ 04-page257 | |
| Date | 1st December 1930 | |
| HS.{Lord Ernest Hives - Chair} FROM R.{Sir Henry Royce} R4/181.12.30. C. to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} C. to HY.{Tom Haldenby - Plant Engineer} PN.{Mr Northey} CAR WORK - 25HP. AND 45HP. THERMOSTATICALLY CONTROLLED SHUTTERS. X.3499. X.7080. X.5080. X5080 The figures shew that in hard running there will be little or no advantage in the thermostat working at a lower temperature. I therefore agree that the higher temperature - 70oC. - shall be adopted, especially now that we have rendered the friction of the shutters very much less, that is, we get wide open without getting to such a high temperature (i.e. the temperature range from full open to closed is less.) Also, it is to be remembered in pointing out to owners that the thermostat can easily be disconnected, and the shutters left in the wide open position during hot weather or in hot climates. Regarding the imperfections of carburation I understand that what SP.{Mr Spinney} calls 'the building up phenomenon' is a difficult one to get rid of, and this is better with hotter water owing probably to the greater heat under the bonnet. At the same time I have instructed that we must have more exhaust heat on to the jacket by making the silencer belonging to this jacket free-r.{Sir Henry Royce} It is possible that the Vortex type of silencer might help to get a free-r exhaust to this auxiliary pipe with sufficient silence. If not it would appear that we must increase the size of the auxiliary silencer. I was very interested in the first of the twin carburetters. It looks quite a good job and I hope it will get on test very soon. One would agree that the intake would appear as if it would be noisy, but this phenomenon is capable of being silenced by a suitable silencer. Probably the one fitted will not be sufficient. R.{Sir Henry Royce} | ||