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).
Engine performance test results comparing fuel consumption with different cylinder capacities, throttles, and ignition systems.
| Identifier | ExFiles\Box 75\2\ scan0259 | |
| Date | 8th September 1921 guessed | |
| Cyl. Capacity 27.5 Cubic Inches Big Throat Water 80° C Battery ignition only used BOTTLES HEAT NO BOTTLES HEAT BOTTLES NO HEAT NO BOTTLES NO HEAT ① ② ③ ④ Time to use Time to use Time to use Time to use 1 qt. of Lbs. 1 qt. of gas Lbs. 1 qt. of gas 1 qt. of gas R.P.M. Air Lbs. Pull Min. Sec. Air Pull Air Pull Air Pull 500 85 105 6 . 52 74 100 6 . 22 81 103.5 6 . 28 78 104 6 . 52 750 73 97 4 . 20 80 97 4 . 27 85 97.0 4 . 26 75 101 4 . 5 1000 78 93.5 3 . 25 81 95.5 3 . 13 86 94.0 3 . 24 78 97 3 . 14 1500 84 83.5 2 . 29 84 84.5 2 . 29 88 82.5 2 . 24 78 87 2 . 20 2000 78 67 2 . 0 86 66.5 1 . 57 88 67.0 1 . 57 78 67 1 . 54 -------------------------------------------------------------------------------------------------------------------------------------------------------------------- Cyl. Capacity 25-25 1/2 Cubic Inches Big Throat Water 80° C Battery ignition only used ⑤ ⑥ ⑦ ⑧ 500 86 108 6 . 18 76 107.5 6 . 28 82 108.5 6 . 30 78 108.5 6 . 15 750 89 104 3 . 54 78 104 4 . 18 84 104.5 4 . 8 78 105.5 4 . 14 1000 90. 100 3 . 14 80 100 3 . 18 84 100.0 3 . 13 78 102.5 3 . 8 1500 90 90 2 . 23 80 89.5 2 . 20 88 86.5 2 . 21 78 88.5 2 . 24 2000 91 72.5 1 . 55 80 71.0 1 . 54 87 71.5 1 . 54 78 71.0 2 . 2 -------------------------------------------------------------------------------------------------------------------------------------------------------------------- Cyl. Capacity 25-25.5 Cubic Inches. Standard Throat Water 80° C ⑨ BATTERY IGNITION ONLY USED ⑩ VAPORIZER FITTED TO ⑪ MAGNETO AND BATTERY USED NO BOTTLES HEAT INLET PIPE VAPORIZER FITTED TO INLET PIPE Time to use Time to use 1 qt. of gas 1 qt. of gas R.P.M. Air Lbs. Pull Air Lbs. Pull Air Pull 500 84 108.0 6 . 38 74 112.0 7 . 5 72 111.0 750 88 102.5 4 . 10 75 107.5 4 . 51 72 107.5 1000 88 98.5 3 . 8 77 102.0 3 . 44 73 105.0 1500 88 89.0 2 . 25 78 92.0 2 . 37 74 97.5 2000 92 71.5 2 . 3 84 79.0 1 . 56 74 82.5 Quarts are U.S. quarts. = 1.2 imperial quarts = .833 imperial quarts C.C. Messrs. Belnap Bagnall Olley Halley Nadin Southern | ||