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).
20 HP engine exhaust tests, comparing standard and modified systems.
| Identifier | ExFiles\Box 48\4\ Scan212 | |
| Date | 1st July 1924 | |
| R.R. 403a (20H) (D.A. 652 20-2-24) J.H.B. Y4238 EXPERIMENTAL REPORT. Expl. No. 4238/488 REF: HS {Lord Ernest Hives - Chair} 2/LG1.7.24. To R. {Sir Henry Royce} from Hs. {Lord Ernest Hives - Chair} c. to CJ. RG. {Mr Rowledge} c. to E. {Mr Elliott - Chief Engineer} DA. {Bernard Day - Chassis Design} c. to EY. WOR. {Arthur Wormald - General Works Manager} 20 HP. EXHAUST TESTS. We have carried out tests with a modified form of exhaust system on the 20 HP. engine. Comparisons have been made on the bench and on the road. We arranged three separate exhaust pipes - one leading away from each exhaust port on the cylinder head into a front expansion box similar to that which we use on the 40/50 HP. The centre exhaust pipe supplied heat to the standard hot-spot. Attached herewith are results of tests. TABLE: H.P. REVS. | STANDARD. | MODIFIED 500 | 10.8 | 10.8 750 | 16.3 | 17.0 1000 | 21.9 | 22.7 1250 | 27.8 | 28.2 1500 | 31.8 | 32.6 1750 | 37.3 | 38.2 2000 | 42.4 | 43.4 2250 | 46.5 | 48.3 2500 | 47.5 | 50.5 2750 | 48.0 | 51.6 3000 | 47.1 | 51.4 Power curve taken on test bench with complete exhaust system of each type. contd:- | ||