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).
Tests of the water circulation, cooling system, and bonnet ventilation, including comparisons with an American Phantom II.
| Identifier | WestWitteringFiles\U\May1930-July1930\ Scan100 | |
| Date | 25th June 1931 guessed | |
| -6- Hs{Lord Ernest Hives - Chair}/Ss.{S. Smith}L/P.II.E.M2.Contd. greater tension (Graph (5)). The Americans use a special canvas rubber fan belt and manual tensioning, which may give them an advantage. Water Circulation. In parallel with the Brooklands tests we carried out some circulation experiments on the test bed, with the complete engine and cooling system. These tests indicate that with the present radiator we have adequate circulation until the top water temperature reaches 95°C. after which point at maximum engine speeds the delivery of the pump falls below that required for the best results. In our previous report Hs{Lord Ernest Hives - Chair}/SsL/17.10.1.30. we shewed that we were on the border line for this trouble, but we still consider that under ordinary road conditions, unless the matrix becomes obstructed, we are not handicapped by circulation. We can undoubtedly improve matters by attention to the radiator outlet and possibly by modifying the pump. We are doing some tests on this. American Phantom ll. We have carried out careful comparative tests on this car at Derby against a production chassis and find that it is normal. It is possible that while in France, it was not running under 100% conditions with regard to ignition advance or fan, but we are confident that it will be up to standard on the present 10,000 miles test. SUMMARY. Bonnet Ventilation. Phantom ll requires as much ventilation as we can | ||