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).
Page detailing tests on induction systems, water jacket temperatures, and their effects on engine power and detonation.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan290 | |
| Date | 12th June 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.D. C EXPERIMENTAL REPORT. -2- Expl. No. REF: Hs{Lord Ernest Hives - Chair}/ACL/LGS.9.25. than either the jacketed pipe or the jacketed pipe and hot spot combined. In view of the possibility of slight power loss occurring through increased piston friction when running with the jacket water cold, which would cause the observed power loss due to the induction pipe temp. to be lower than actually, we took power readings on the standard engine with hot and cold water jacket and could get no appreciable difference. Therefore the power loss shown on Sheet 1. can be taken as due to the induction pipe temperature. The other curves given on Sheet 2. are comparisons of the two induction systems under the same conditions i.e., water temperature average 35°C, hot spot disconnected and short exhaust pipes to each port. The induction pipe in the cylinder head shows an advantage over the standard but the gain is only small and is entirely outweighed by the loss due to the hot induction pipe when the engine is operating at normal temperature. The distribution - by observation at the ports - when run cold, is very similar to standard. Apart from the power we find that the high induction temperature considerably increases the detonation. This is clearly demonstrated by varying the water jacket temperature when the engine is running. IGNITION TIMING AND DETONATION. It was found that when both ignitions - magneto operating plugs in standard position and battery plugs on the exhaust port side (right hand) - were synchronized contd :- | ||