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).
7,100 miles of running tests in France for the Wraith III No.1 Unit.
| Identifier | ExFiles\Box 108\1\ scan0149 | |
| Date | 3rd September 1937 | |
| To: [crossed out text] from Rm{William Robotham - Chief Engineer}/IMW.{Ivan M. Waller - Head of Chateauroux} (Handwritten in red over the crossed out text: Rumour, h'pwr, Conclud) Rm{William Robotham - Chief Engineer}/IMW.{Ivan M. Waller - Head of Chateauroux}4/AP.3.9.37 TESTS IN FRANCE -.26.C.Vl.{V. Lewis / Mr Valentine} 25/30. Report on 7,100 miles running - Specification HPS{Horace Percy Smith - Experimental Factory Mgr}/CF/19 & 24/C/37 and 2,5,9,16,22,26/1/37 Engine. Wraith III. No.1.Unit. The performance was good and adequate for a car of this type with limousine body. Acceleration was superior to standard 25/30 and the maximum timed mean speed over a kilometer was 78 m.p.h., which was better than 22.C.V. by 3 m.p.h. An unsatisfactory engine mounting prevented a true noise standard being given, but the engine became considerably more noticeable directly 70 m.p.h. was exceeded. The general impression was that an overdrive, together with a lower direct and a second gear between the present second and third would improve the all round performance and reduce the amount of gear changing necessary in hilly country, at the same time giving the engine an easier time. The maximum oil temperature reached with sustained speed was 126°C. during which the oil pressure remained at 25 lbs/sq.in. The oil consumption was as follows, using Duckham's N.P.3. On 1st. gallon - 721 miles. " 2nd. " - 1202 " " 3rd. " - 988 " " 4th. " - 1183 " " 5th. " - 995 " " 6th. " - 980 " Average consumption 1011 m.p.g. The average petrol consumption was 11 m.p.g. which compares unfavourably with 12.4 m.p.g. on 22.C.V. in France. continued | ||