Data tables comparing engine heat flow and horsepower with clean vs. carbonised engines, and with aluminium vs. cast iron pistons.
| Identifier | WestWitteringFiles\K\September1923\ Scan30 | |
| Date | 1st September 1923 guessed | |
| SHEET 5. CLEAN AND DIRTY ENGINE - CAST IRON AND ALUMINIUM PISTONS. EFFECT OF CARBON DEPOSIT ON HEAT FLOW TO COOLING WATER. COMPRESSION RATIO FOR THESE READINGS 3.9. Carbonised engine. R.P.M. | HP. | Ht. flow to jackets. B. Th. U's. min. 500 | 21.87 | 1328.4 750 | 32.38 | 1912.5 1000 | 43.5 | 2079.0 1250 | 53.9 | 2608.0 1500 | 62.7 | 2948.0 1750 | 69.6 | 3307.0 2000 | 73.3 | 3654.0 Clean engine. HP. | Ht. flow to jackets. B. Th. U's. min. 23.1 | 1660 33.6 | 2250 45.4 | 2970 56.7 | 3167 66.2 | 3402 74.7 | 3780 77.3 | 3982 HEAT FLOW WITH CAST IRON AND ALUMINIUM PISTONS COMPARED. Alum. pistons. R.P.M. | HP. | B. Th. U's. min. 500 | 23 | 1475 750 | 34 | 2025 1000 | 45.5 | 2300 1250 | 55.5 | 2780 1500 | 67.0 | 3060 1750 | ---- | 3380 2000 | ---- | 3980 Cast iron pistons. HP. | B. Th. U's. min. 22.3 | 1413 34.25 | 1925 45.7 | 2310 57.1 | 2745 67.2 | 3100 73.4 | 3440 97.7 | 3600 Note :- Carburutter for each of these readings was the same viz. set for normal running. | ||
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).