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 performance during fast motor boat runs, focusing on the cooling and exhaust systems.
| Identifier | ExFiles\Box 174\4\ img010 | |
| Date | 1st May 1931 | |
| Hs{Lord Ernest Hives - Chair}/Crmel/ADD.5.31 contd. -8- The Parana River was very choppy when the record was run and not at all ideal for fast motor boat work; the majority of the Argentine people were amazed at the speed we set up under the unfavourable conditions. The engines ran faultlessly during the fast runs, the R.P.M. 3000 and boost pressure 12 lbs/sq.in. was satisfactory. These figures corresponding with the maximum figures of the engine power curve for 2000 B.H.P. allowing for a loss of approx. 100 H.P. per engine for the high air temperature 35°C. the actual H.P. developed from each engine was around the 1900 mark. WATER COOLING. The water system functioned perfectly as far as controlling temperatures. Tilcock being highly satisfied with the controllability of the temperatures up to a point. The maximum outlet temperature could not be allowed to increase over 65°C. as excessive pressures were built up in the scoops. At 65°C. outlet the scoop pressure was 8 lbs/sq.in. The scoop should be slightly reduced in area for the next trials to lessen the pressure. OIL COOLER. The time running at high speeds was not sufficient to test the total cooling capacity of the cooler which functioned satisfactorily for these runs. The removal of the exhaust supply from the cooler feed did not cause any high pressure to build up, the maximum pressure at high speed being 4 lbs/sq.in. The new exhaust scoop stood up exceedingly well and was quite O.K. when inspected after the record run. The petrol system gave no trouble throughout all the runs. The K.L.G. 618 sparking plugs did not show any signs of overheating after the high speed. Hs{Lord Ernest Hives - Chair}/Crme. | ||