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).
Investigation into the cause of a 'power roar' from the Goshawk 11 induction system.
| Identifier | ExFiles\Box 180\M1\1\ img069 | |
| Date | 1st October 1921 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to EY. c. to KP. c. to Wor.{Arthur Wormald - General Works Manager} ORIGINAL hs{Lord Ernest Hives - Chair}2/LGS.10.21. GOSHAWK 11, INDUCTION SYSTEM. - POWER 'ROAR' With reference to the roar we get from the induction system. We have investigated this further and find that it cannot be cured by changing from butterfly to piston type throttle. We find that Goshawk 1. Car which has practically the same design of carburetter as Goshawk 11. is entirely free from this noise in fact, Goshawk 1. is very much better than the standard 40/50 H.P. for absence of noise from the induction system. We have also tested the Marmon Car. The Marmon car as you are aware, has the inlet ports arranged the same as Goshawk 11. That car does not have this noise. it is equally as good, if not better than the 40/50 H.P. in this respect. In order to prove that the noise we complain of is actually coming from the carburetter and induction system, we towed Gosh-awk 11. car with a very long induction pipe fitted so that the carburetter was under the rear seats. If we did this, the noise could not be heard. This, we consider, cuts out any possibility of the noise coming from vibration periods or exhaust or any other part of the engine. It is a noise which must be overcome. Our next move is to fit an induction pipe and carburetter of the same design as is on the Marmon Car. If it still remains then the only thing we can think of to be the cause of it, is the shape of the ports in the cylinder head. Hs.{Lord Ernest Hives - Chair} | ||