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).
Road and dynamometer test report comparing a car's performance against a Stutz and a Phantom model, noting issues with an overheating axle.
| Identifier | ExFiles\Box 23\5\ Scan060 | |
| Date | 18th July 1925 guessed | |
| contd :- -B- favourable comparison with our 20 HP. and that is between 20 and 30 m.p.h. over a really bad pot-holey road. The Stutz is a trifle steadier. When sitting in the driving seat one gets the impress- ion of a well-sprung car, but this impression is quickly changed when sitting in the rear; the front is well sprung but with inade- quate shock damping. Brake horse-power at road wheels. We give below the result of an attempt to obtain a power curve on the dynamometer. While running at 2000 r.p.m. it was noticed that the rear axle casing was extremely hot, so hot that the paint was blistering, accordingly the test was stopped and the axle allowed to cool. A stream of water was played on the axle and a second attempt was made to obtain figures above 2000 r.p.m. The axle again became hot almost immediately, before it was possible to obtain any results, so it was decided to aban- don any further attempts. Consequently the curve above 2000 RPM. is what we imagine, probably optimistically, it would be from the information given in the Instruction Book that the engine power peaks at 110 B.HP. at 3,600 r.p.m. The Phantom curve given is the power developed by the car 98-NK at the time the acceleration tests, given previous- ly were made. For comparison purposes the two curves have been reduced to a power-road speed base, the Stutz engine r.p.m. also being indicated. While running on the dynamometer, the engine smoothness while running at full throttle was very noticeably good, certainly definitely smoother than the Phantom contd :- | ||