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).
Successful dynamometer test of the gearbox, noting oil loss and road performance.
| Identifier | ExFiles\Box 179\3\ img078 | |
| Date | 17th March 1932 | |
| R.{Sir Henry Royce} From He/Gr.{George Ratcliffe} c. to SS.{S. Smith} c. to W. H.{Arthur M. Hanbury - Head Complaints} c. to Ry. P.11 of G/Ldn. X7310 We have just completed a successful dynamometer test on this gear box. The car was run on each forward gear for half an hour at 3000 R.P.M. Top, 3rd, and 2nd, gears were run full throttle giving a road wheel HP of 105. We started to run 1st gear full throttle but with the low rating & strains of subsequent wind up of the axle and angle of the mechanical joint there is torque of about 8000 lbs ft. after 5 minutes the rear universal ran very hot lost a considerably quantity of oil by burning and because very out of true. We therefore finished the test at 2/3 full torque, reverse gear was run for 10 minutes on 1/4 to 1/3 throttle. It should be added that the engine exhaust, both carburettors and oil O/T readg. no trouble of any kind was experienced with the gear box, nor were there any oil leaks although the oil temperature reached 112C. On the road 3rd gear is very quiet but the change from top to 3rd is not so good as on the saloon. The gear lever has to be moved abruptly for a good change. We are therefore trying a smaller cone angle (8° instead of 10°) and also a lesser cone angle so that it shall be easier to have the sliding members become synchronised. He./Gr.{George Ratcliffe}/lls. | ||