Revised exhaust system without a front expansion box for the Wraith III model.
| Identifier | ExFiles\Box 8\8\ 08-page70 | |
| Date | 5th November 1938 | |
| 623 DV/NS. {Norman Scott} [Strikethrough] C. Rm. {William Robotham - Chief Engineer} [Strikethrough] c. Rm {William Robotham - Chief Engineer} /Wym. {G. Harold Whyman - Experimental Manager} [Strikethrough] c. Da {Bernard Day - Chassis Design} /JD. {J. Draper - Frames} [Strikethrough] DA. {Bernard Day - Chassis Design} 8/G.5.11.38. [Signature Aill] [Signature WYMAN] WRAITH 111 - REVISED EXHAUST SYSTEM WITHOUT FRONT EXPANSION BOX. Please receive herewith the following designs, showing the complete revised exhaust system:- E.CD.872 - 1/2 scale Layout of Exhaust System - Wraith 111. E.CD.879 - Front Silencer (3 way Tuning) - Wraith 111. E.CD.890 - (Sheet 1) Downtake and Intermediate Pipe (Plan View). Wraith 111. E.CD.890 - (Sheet 2) Downtake and Intermediate Pipe (Elevations). Wraith 111. E.CD.899 - Tail Pipe (1.750 diameter). Wraith 111. These new designs are made in accordance with the exhaust system already tried experimentally, and reported in Rm {William Robotham - Chief Engineer} /Wym. {G. Harold Whyman - Experimental Manager} 12/JH.18.8.38, the principal differences from the standard Wraith 111 exhaust system being as follows:- (1). The front expansion box is omitted and the downtake pipe which is now not lagged is made in .104" thick material and carried through to the front silencer, new supports are supplied for the downtake. (2). The front silencer is as shown on the diagram Rm. {William Robotham - Chief Engineer} 552 being a three way tuning with perforated tubes, a new support is also shown for this. (3). The material for the front silencer and tuning pipes is called for as Staybrite. Should the heat-resisting steel now being tried turn out all right, the [Strikethrough] material will be changed to this. (4). The diameter of the tail pipe has been increased from 1.500 to 1.750", and its rear support bracket is altered to suit. (5). The rear silencer is standard. Will Da {Bernard Day - Chassis Design} /JD. {J. Draper - Frames} please note the alterations to the positions of some of the holes in chassis frame to accommodate the revised intermediate pipe and also that slight alterations to the oil pipes for centralised lubrication will be necessary as stated on E.CD.879. These designs should be detailed and issued experimentally. DA. {Bernard Day - Chassis Design} | ||
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).