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).
The performance of an exhaust system fitted to car 103-MC, discussing hill climbing and silencer cutout effects.
| Identifier | ExFiles\Box 71\3\ scan0322 | |
| Date | 12th June 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.D. +8950 EXPERIMENTAL REPORT. Exptl. No. REF: Hs{Lord Ernest Hives - Chair}3/LG11.9.25. To BJ. from Hs.{Lord Ernest Hives - Chair} EXHAUST SYSTEM FITTED TO 103-MC. +8230 +8950 The last time 103-MC was at Derby, we carried out tests which show that the performance of this car for hill climbing was below the standard. This was the case even with the standard exhaust system. We could not find anything obviously wrong with it. It would appear however desirable to send it in for attention when it can be spared. We attach power curves taken of the silencer. It will be seen that with the cutout open the power is identical to the present standard silencer. There is no reason why it should be any different. With the cutout closed, there is no difference in power up to 1500 r.p.m. which is equal to 45 m.p.h. The slight drop at 2000 revs., we do not think this could ever be measured on the road. Above 60 m.p.h., if max. speeds are desired, one would expect the cutout to be used. The difference caused by the silencer can always be measured by opening the cutout. Hs.{Lord Ernest Hives - Chair} | ||