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).
Scheme to add a hot spot to the 40/50 HP induction pipe.
| Identifier | WestWitteringFiles\F\February1921\ Scan52 | |
| Date | 18th February 1921 | |
| To Ph. from E.{Mr Elliott - Chief Engineer} Copy to EPC. [Stamp: RECEIVED FEB 18 1921] [Stamp: ORIGINAL] E1/G17/2/21 X.4305 RE 40/50 H.P. HOT SPOT INDUCTION PIPE. We send you herewith drawing No. Lec.1350 showing a scheme for providing a hot spot on the tee joint of the 40/50 H.P. induction pipe. This is the simplest scheme which can be thought of, and the one involving the least possible change to existing cars. The manifold portion of the induction pipe has been decreased by Mr. Royce, from 2" to 1¾" diameter, with a view to improving the distribution. Therefore a new induction pipe complete will be required, although the existing standard exhaust boxes will be used, as the exhaust pipe couplings have been made so that they screw into the exhaust plug holes in the ends of the exhaust boxes. The jacket has been formed by making a complete casting of the tee joint, and Nos. 3 and 4 induction pipe bends. The remainder of the manifold is attached to this central casting by brazing as heretofore. Steel tubes should be used for the manifold with a view to making the pipe sufficiently strong to resist the torsional deflection produced by the weight of the carburettor. It is understood that although the carburettor has a sheet metal support, it is found in practice that the induction pipe manifold becomes twisted. A sheet metal guard is provided as a protection for the magneto ignition leads. The hot air pipe has been shewn coupled up to this guard, but should not be used unless proved beneficial by experiment. It is not thought that the guard and pipe arranged as shown, is a very efficient hot air device, but experiments should be made to determine whether a good supply of hot air is necessary or not in addition to the effect of the hot spot induction pipe. E.{Mr Elliott - Chief Engineer} | ||