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).
Data table showing results from starter motor tests, specifically efficiency ratios.
| Identifier | ExFiles\Box 64\1\ scan0281 | |
| Date | 14th June 1928 | |
| STARTER MOTOR TESTS. FORM 5. EFFICIENCY RATIOS. G.2. | c | ΦE | Φe | ΦB | ΦT | Φs/ΦE = es/E | ΦT/ΦB = TT/TS | Φs/ΦE = η | Φs/Φe | |---|---|---|---|---|---|---|---|---| | 20 | - | - | - | - | - | - | - | - | | 30 | - | - | - | - | - | - | - | - | | 40 | 183.0 | - | 167.8 | 26.05 | .917 | .155 | .142 | - | | 50 | 201.5 | - | 177.2 | 60.6 | .880 | .342 | .3005 | - | | 60 | 216.5 | - | 187.3 | 84.4 | .865 | .451 | .390 | - | | 80 | 250.5 | - | 200.0 | 119.0 | .798 | .595 | .475 | - | | 100 | 283.5 | - | 207.5 | 145.8 | .732 | .702 | .514 | - | | 120 | 324.0 | - | 216.2 | 162.2 | .667 | .751 | .501 | - | | 140 | 374.0 | - | 222.5 | 175.1 | .595 | .787 | .468 | - | | 160 | 453.0 | - | 227.3 | 186.9 | .502 | .822 | .412 | - | | 180 | 580.0 | - | 231.7 | 197.6 | .400 | .854 | .341 | - | | 200 | 781.0 | - | 235.5 | 206.0 | .3015 | .875 | .264 | - | | 220 | 1159 | - | 238.0 | 213.0 | .205 | .895 | .184 | - | | 240 | 2395 | - | 240.2 | 219.0 | .1002 | .9125 | .0915 | - | 14.6.28. | ||