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).
Road test data recording bump measurements at speeds of 50 and 55 MPH.
| Identifier | ExFiles\Box 49\1\ Scan162 | |
| Date | 18th March 1920 guessed | |
| SPEED OF CAR 55 MPH. 8th. bump. - 2.10. 9th. " - 2.05. 10th. " - 2. 11th. " - 1.83 12th. " - 2. 13th. " - 1.90 14th. " - 1.80 15th. " - 1.75 16th. " - 1.65 SPEED OF CAR ABOUT 50 MPH. 1st. bump. - 2.05 2nd. " - 1.93 3rd. " - 1.86 4th. " - 1.77 5th. " - 1.85 6th. " - 1.68 7th. " - 1.65 8th. " - 1.59 9th. " - 1.51 10th. " - 1.38 11th. " - 1.54 12th. " - 1.37. (Sgd). C.de S. | ||