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).
Problem with the 20 HP exhaust system and the proposed solution of a front expansion box.
| Identifier | ExFiles\Box 6\7\ 07-page047 | |
| Date | 9th April 1929 | |
| To DA.{Bernard Day - Chassis Design} from Hs{Lord Ernest Hives - Chair}/Rs.{Sir Henry Royce's Secretary} X5230 Hs{Lord Ernest Hives - Chair}/Rs{Sir Henry Royce's Secretary}2/DG9.4.29. 20 HP. EXHAUST SYSTEM. X5230 with reference to DAL/M6.4.29. The trouble with the 20 HP. exhaust system is exactly the same as that on the S.S., due apparently to the 3-port exhaust system coupled with the stream line flow through the Prince of Wales feathers, there is a very marked exhaust period between 40 and 50 m.p.h. very much the same as the one you heard on our experimental cars here. The only way that has been approved by R.{Sir Henry Royce} for curing this is the front expansion box, and therefore we should like a scheme on these lines in the absence of any better arrangement. Hs{Lord Ernest Hives - Chair}/Rs.{Sir Henry Royce's Secretary} | ||