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).
Performance tests of the 'Monsoon' car at the Brooklands track.
| Identifier | ExFiles\Box 3\4\ 04-page176 | |
| Date | 6th February 1933 | |
| To R.{Sir Henry Royce} from Ha/Ma. c. C. Mr. Wor.{Arthur Wormald - General Works Manager} c. S. Mr. Ha. c. O.{Mr Oldham} Mr. HY.{Tom Haldenby - Plant Engineer} c. C. Mr. Hives. MONSOON. BROOKLANDS TESTS. We had this car on the track on the 2nd. inst. The weather was excellent. In the condition as tried by us, i.e. No cut-out, standard front wings - our best lap was 87 m.p.h. We found that, though slightly under geared for the track, we could gain rather over 3 m.p.h. by removing the front wings, and about 2 m.p.h. by a cut out. The car was geared to do X m.p.h. at 4330 r.p.m. The critical speed of the crankshaft fitted was about 4600 r.p.m. It had Chrysler weights. With the 8-8 weight scheme, which is being produced, the critical speed would be raised another 150 revs. When running without front wings, we could definitely feel the fringe of the period. For ordinary work, however, we think that the 10/41 axle fitted will be ideal with the saloon body. The engine performed faultlessly, the 14 mm. plugs showing no signs of pre-ignition, though they are equally satisfactory for town work. The suspension was good, but higher damper loads would naturally have been an advantage, as the track was very rough. Nevertheless the car held the track better than any we have tested on Brooklands. The one point for criticism was the steering. This had not a sufficiently positive feeling of directional stability at maximum speeds on the rough surface. The characteristic is not so noticeable on the road unless the surface is bad. We were running with 4½o backward pivot lean which is about the limit if low speed wobbles are to be avoided. Tests have been made on J.III. that an increase in king pin angle greatly improves matters, and a separate report has been issued. The point was previously dealt with on the Phantom I in our Ha/Mil/T.29.9.20. copy attached. The oil temperature inlet to the bearings reached 115oC. after three laps all out. The temp. did not exceed 70oC on the road, to and from the track, air temp. 5-10oC. | ||