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).
Letter from Rolls-Royce of America discussing experiments and suggestions for improving the hot spot throttle design.
| Identifier | ExFiles\Box 50\3\ Scan112 | |
| Date | 21th July 1921 | |
| X4305 CC Mr. Hives Mr. Nadin Oyl - G 21721 July 21, 1921 Mr. Claude Johnson, Managing Director, Rolls-Royce Ltd., London, England. Attention: Mr.F.H.Royce. Dear Sir:- Re: Hot Spot Throttle With reference to Mr. Royce's letter R3/G1.7.21 with LeC-1418 enclosed, from Mr. Hives' letters it would certainly appear that this form of hot spot was most readily adapted to the existing car. Mr. Hives made an experiment while here in January of taking a 5/8" pipe from the exhaust box to the existing throttle jacket, throwing away the exhaust under the car. He did not get sufficient heat by this device to make any appreciable improvement in the running. We would therefore suggest that a 1" pipe for the exhaust gas would seem more likely to supply sufficient heat than the 3/4" pipe shown on LeC-1418. We would also suggest that an interchange of gas between the two exhaust boxes seems better than a straight flow of exhaust in preventing excessive heat at high speeds, the less time period of the interchange at high speeds reducing the flow of gases. We have not definitely proved this point, but it would seem to be easily tried out. Further, we would suggest that it would be better to jacket the throttle equally all round and on both end faces rather than on one side only as at present, since the latter arrangement is liable to produce dry gas at one side of the pipe and wet at the other, a condition we actually got last winter when we used a "hotpatch" on the Tee piece of the manifold. Yours truly, ROLLS-ROYCE OF AMERICA, Inc. MO/G Per M.{Mr Moon / Mr Moore} Olley | ||