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).
Engine cooling tests comparing performance with and without a bonnet, alongside notes on various mechanical repairs.
| Identifier | WestWitteringFiles\I\June1922\ Scan17 | |
| Date | 14th June 1922 guessed | |
| 43 Bonnet and the results were as follows Water temp at start With bonnet 55° Without 75° " finish " 100 " 95° Distance of hill " 3 miles " 4 miles (top) Height climbed " 1350 ft " 1900 feet Speed during climb " 20 to 30 MPH " 20 to 30 MPH Gear used " 2nd " 2nd I do not know how much difference is due to the wind cooling the engine and pipes direct but I think it is worth while to try a bonnet with windows cut in the sides like the 40/50. Perhaps this could be done on 59H and combined with the better fan should make a great improvement.] The joint between the carburetter and the cylinder gave out yesterday. This was made of two layers of sheet rubber and the rubber had rotted away and broken. We have made a new one of aluminium sheet as we have no C + A washer for the job. [We found the bolt which holds the near side rear engine foot down was loose and this was tightened.] The C A V dynamo has had to be removed owing to its making | ||