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).
Design and implementation of new bonnet louvres for the Phantom to solve overheating problems.
| Identifier | ExFiles\Box 24\5\ Scan100 | |
| Date | 8th August 1925 | |
| To BY, from DA.{Bernard Day - Chassis Design} c. to Hs.{Lord Ernest Hives - Chair} x766 DA{Bernard Day - Chassis Design}2/M8. 8. 25. RE. NEW PHANTOMCodename for PHANTOM I LOUVRES. X. 8260 X. 766 X. 4214 Referring to BY/C8/K17.7.25., we believe that R.{Sir Henry Royce} does not approve of the general use of louvres, and hopes that we shall only be compelled to fit them in a few cases where over-heating is serious. When we do fit them however we should like to have as nice a scheme as possible, and we suggest that the next thing to do is to make a bonnet with louvres similar to the Hispano - that is to say - the same pitch and the same shape. A question was raised down here as to whether the top line of the louvres should be horizontal, or whether it should be parallel to the hinge. It is rather difficult to be certain as to the best arrangement, and we suggest that a compromise should be struck, and the top line of the louvres should rise .250" from the front to the back, this being half the standard rise of the hinge. This might have the effect of preventing the top line of the louvres appear ing to absolutely fall, while at the same time it did not over emphasise the slope of the hinge. We suggest that this bonnet should be made and fitted to the first available finished car coming down here. It is impossible to get a good impression from a chassis with a test scuttle. CWB. has sent us a number of suggestions for louvres of various types. We think perhaps it is not necessary to make all of these as the fine pitch louvres like the Hispano may do all that is required. Everybody should of course have a look at it before it is finally adopted. DA.{Bernard Day - Chassis Design} | ||