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).
Comparison of Girling and R.R. brakes on car 3.B.IV against a standard 4 1/4 litre customer's Bentley.
| Identifier | ExFiles\Box 82\5\ scan0211 | |
| Date | 29th April 1938 | |
| COPY FOR FILES. To Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/FD.{Frank Dodd - Bodies} 206 29.4.38. 3.B.IV. GIRLING AND R.R. BRAKES. The brakes on this car have been compared with a standard 4¼ litre customer's Bentley. Our comments are as follows :- The standard Bentley braking from 60 m.p.h. to rest was much better than 3.B.IV when tried under the same conditions, i.e. equal tyre sizes. The braking figure of 3.B.IV was improved when the 6.50 x 17" tyres were fitted but even then this car is not so good as the standard car. Below 60 m.p.h. there is very little difference in the braking efficiency of the two cars and the larger tyres show to advantage only from high speeds. Speedometer checked to 2%. Stopping from 60 m.p.h. Customer's car. 5.50 x 18 tyres. 111 ft. pedal pressure 115 lbs. " " " " 3.B.IV. 6.50 x 16 tyres. 120 ft. pedal pressure 110 lbs. " " " 3.B.IV. 5.50 x 18 tyres. 135 ft. pedal pressure 90 lbs. Cont'd.{John DeLooze - Company Secretary} | ||