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).
Power loss in the EAC engine due to its 6-cylinder exhaust manifold.
| Identifier | WestWitteringFiles\L\Jan1924-March1924\ Scan181 | |
| Date | 1st March 1924 | |
| R.R. 403A (40 H) (SL 42 12-7-23). J.H., D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT ORIGINAL Expl. No. 9771 9230 REF: Hsl/LGS.3.24. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. RH.{R. Hollingworth} c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. to EY. SOR.✓ c. to FN. ✓ SECRET. EAC. ENGINE POWER. Our tests prove that we are losing considerable power with the 6-cylinder exhaust manifold on the EAC. engine. If we test with open exhaust from the cylinders, a xxxxx percentage of the exhaust gases goes back through the carburetter and the power obtained is approximately the same with the manifold on or off. It is necessary either to run with straight pipes to make sure of getting the exhaust clear, or else use an elaborate system of shields. We are building up a larger exhaust manifold with a larger pipe down from the engine. The Hispano engine has a 6-cylinder exhaust manifold with a 3.5" pipe leading from it. It is possible that the proposed modifications to the standard 40/50 exhaust system when the generator is put on the engine, may need alteration. We expect to have an engine running tomorrow with this scheme arranged temporarily. contd:- | ||