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).
Initial tests to determine the efficiency of a different type of piston compared to the standard cup leather.
| Identifier | ExFiles\Box 66a\4\ scan0113 | |
| Date | 16th February 1926 guessed | |
| contd :- -2- Our initial tests were therefore made with the object of dis-covering whether another type of piston would produce a better efficiency than the present standard cup leather. Our tests of efficiency were carried out at 1000 r.p.m. with an oil pressure of 13 1/4 lbs/sq.in. and a temperature of 60°C. We consider that this is quite an average running condition. After a burst of speed, the oil temperature will rise and we have found many reach 90°C. Under these conditions the efficiency of the piston may be expected to fall some 25% from figures we have obtained. Therefore the actual power available from each type of piston under extreme conditions will be about 25% less than the figure given in our comparative tests. contd :- | ||