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).
Potential modifications for increased cooling for the 25 HP and 45 HP models.
| Identifier | ExFiles\Box 24\5\ Scan272 | |
| Date | 4th July 1930 | |
| X766 Hs.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} c. Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. By.{R.W. Bailey - Chief Engineer} C. RI/M4.7.30. X.766 X.1085 X.7250 X.5250 25 HP. & 45 HP. MODIFICATIONS FOR INCREASED COOLING. I do not like the idea of cutting away the front apron because of the tendency for water, mud, and dust, to enter under the bonnet. My impression is that the original scheme of front and rear shutters is still the best arrangement because with these one can keep the engine house warm in winter and cool in summer. The alternative arrangement to this is to use horizontal louvres which I believe could be made to add to the lengthy appearance of the bonnet, and would prevent one seeing into the engine house, and would probably let out less sound because of it being less direct. It has occurred to me that our radiator tubes may be more effective if they were larger cross section considering their present length. I should not expect very much, if any, improved cooling from this but we might save some weight and money, and with a coarser tube we might have a bigger waterway. I suggested many months ago ample vertical waterways and square tubes, but I have not seen any test reports of the experimental radiator that was to be made to this suggestion. Regarding the question of further cooling one can only think that we have reached nearly the limit of the size of radiator, and it would be interesting to have a comparison with other cars of equal BHP. to our 25 HP. and 45HP. One would be specially interested in the Maybach 12 cyl. the somewhat smaller capacity of the Hispano, and the American cars with 8 and 16 cyls. We should expect that the greater number of cylinders would be more difficult to cool, but generally these engines are less in cubic capacity, our 45 HP. being one of the largest in production that we remember at the moment. R.{Sir Henry Royce} | ||