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).
Results and future plans for cooling tests on 25 HP and 40/50 HP engines, including the Phantom II.
| Identifier | ExFiles\Box 24\5\ Scan277 | |
| Date | 1st July 1930 | |
| X766 To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. Sg.{Arthur F. Sidgreaves - MD} c. Wor.{Arthur Wormald - General Works Manager} c. Ev.{Ivan Evernden - coachwork} C. Hs{Lord Ernest Hives - Chair}/Rml/ADLO.7.30. X.788 X.766 X.7250 X.5250 X.7260. COOLING TESTS 25 H.P. and 40/50 HP. With reference to R2/M1.7.30. R1/M4.7.30. You will see from our 2nd Brooklands report that given a 100% fan drive and fuel supply the Phantom II cannot really be considered undercooled if the customer will open his bonnet shutters. Since we find so little difference between 7 mm. and 7 1/2 mm. tubes it appears that we cannot hope to gain much from further increase in tube size. Our own feeling is that there is little difficulty in getting the heat from the water to the radiator tubes but great difficulty in getting heat from the tubes to the air. For this reason we want to try the American dented tubes with a view to getting the maximum amount of air turbulence with our short tubes. We know that they were tried 10 years ago but conditions have altered. We agree that we must test with radiator shutters removed, we did this seven years ago and could detect no difference, but speeds are much higher now. We will try varying the gear ratio with the minimum and maximum size of wheel attainable. | ||