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 plotting the angle of rotation against torque from torsion tests on various front springs.
| Identifier | ExFiles\Box 52\2\ Scan141 | |
| Date | 31th March 1927 guessed | |
| TORSION TESTS ON FRONT SPRINGS. Y-AXIS: ANGLE OF ROTATION X-AXIS: TORQUE IN 1000 LBS - IN. DATA POINTS: O4, A4, B4, B3, A3, D3 LEGEND: A = FIRTH'S SPRING 1100 LBS TOTAL LENGTH 43.5 INS B = WOODHEADS EQUAL SPRING 1100 LBS TOTAL LENGTH 42.000 INS D = " SPECIAL " " 43.500 INS THIS SPRING HAS FOUR REBOUND LEAVES & CLIPS [Diagram showing spring assembly with pointers to components labelled '= 4' and '= 3'] * CONVERTED READINGS GIVING THE PRE-FRONT BRAKE SPRING THE SAME RATING AS THE POST FRONT BRAKE SPRING | ||