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).
Graph comparing the torque versus current for three different starter motors.
| Identifier | ExFiles\Box 50\2\ Scan120 | |
| Date | 24th April 1920 | |
| By Ap. 24 '20. I. X 4304 TORQUE OF 3 STARTER MOTORS CURRENT. Torque ft-lbs. 0 4 8 12 16 20 24 Amps. 0 100 200 300 400 500 600 BOSCH BIJUR. WESTINGHOUSE PRACTICAL MAXIMUM VALUE OF WORKING TORQUE | ||