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).
Comparing the matrix dimensions of various cars.
| Identifier | ExFiles\Box 24\4\ Scan109 | |
| Date | 12th July 1923 | |
| R.R. 402A (40 H) (SL 42 12-7-23). J.H., D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT. Expl. No. 1751 REF: Hs{Lord Ernest Hives - Chair}3/LGS.10.23. COMPARISON OF MATRIX DIMENSIONS OF CARS. We have endeavoured to make reasonable comparison of the matrices of the cars we inspected. We could not make a comparison against HP. developed at a given road speed as we should have wished as we had no means of obtaining the HP. curves of the cars in question - (we have done this for 40/50 and 20 HP.) We have, however, compared the radiators on a 'displacement' basis, and 'displacement per mile on direct drive' basis. We consider the latter to be the better comparison as otherwise the cars such as the 'Fiat' with a low gear ratio are apt to appear disproportionately well cooled. It will be seen that the 20 HP. is about up to the average of the better class cars. The 40/50 HP. on the other hand, appears to be badly off in every way. The Hispano, having much the same displacement, is perhaps, the best car for comparison, and indicates the adverse conditions under which the 40/50 HP. operates. The difference between the 40/50 and the 20 HP. is rather exaggerated in these comparisons but it must be remembered that the maximum M.E.P. of both engines is at about 750 r.p.m., in which circumstances the 40/50 would be climbing at 20 m.p.h., while the 20 HP. would only be doing 15 m.p.h. The lower air velocity through the 20 HP. radiator therefore, somewhat counterbalances its advantage in size. Hs{Lord Ernest Hives - Chair}/Bm. | ||