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).
Car performance tests, a component failure, and engine running observations.
| Identifier | ExFiles\Box 5a\3\ 03-page169 | |
| Date | 14th December 1931 guessed | |
| (3) (18) Smith electrical petrol gauge failed to read correct amount of petrol after 7,500 miles. The Acceleration figures of the car are as follows :- M.P.H. Secs Average. 10 - 20 ... 5.0 20 - 30 ... 5.0 30 - 40 ... 5.0 40 - 50 ... 6.5 50 - 60 ... 9.0 60 - 70 ... 14.0 The Braking tests with the brakes hot are as follows:- From 20 M.P.H. to 10 M.P.H. ... 12 feet. 30 M.P.H. to 10 M.P.H. ... 34 feet. 40 M.P.H. to 10 M.P.H. ... 76 feet. 50 M.P.H. to 10 M.P.H. ... 134 feet. 60 M.P.H. to 10 M.P.H. ... 225 feet. 70 M.P.H. to 10 M.P.H. ... 320 feet. ------------- ENGINE UNIT NO. C.XI. E.57271 Crankshaft S/NCR. 4 E.57287 Small Balance Weights. 4 E.57288 Large Balance Weights. Rear Flange to suit Thin Web Flywheel. Comp. Ratio 5.7 to 1. We have found that with the diamond mounting the smoothest running is obtained by having the engine feet just balanced by the rubbers (i.e. no compression), and the torque reaction dampers set at 3 lbs. friction load. The fabrics of these dampers must be oiled as when they are in a dry state the initial movement causes a knock, which is very misleading and would be taken for a hydraulic damper knock. We tried the spring plates on the rear engine feet, but they caused increased torque reaction and slight booms in the body. There have been slight periods of the engine at speeds of 38 - 42 and 60 M.P.H. The engine has started up easily from cold, and slow running has been even, power and acceleration remained good. Detonations became noticeable after a mileage of 5,000 and have increased in volume during the further mileage. It has been necessary to retard the ignition 5 notches on the quadrant to be free from them up to speeds of 40 M.P.H. Loco petrol has been used which is supplied by the Standard Oil Co. It is the standard | ||