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 Phantom II exhaust system and the need to reduce back pressure.
| Identifier | ExFiles\Box 14\6\ Scan198 | |
| Date | 13th June 1931 | |
| To R.{Sir Henry Royce} From Ha/Rn.{Mr Robinson} c. to Ng. Nor. c. to Da.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} c. to Hy.{Tom Haldenby - Plant Engineer} 87230. Ha/Rn.{Mr Robinson} 3/KT. 13. 6. 31. EXHAUST SYSTEM P.II. We find that as we increase the power output on the Phantom engine, our loss in the exhaust system increases very rapidly. With a power output of 180 BHP. we lose 40 HP. in the silencer at high speeds. This largely confirms the results we have obtained on the 20/25 HP. and is due to the high degree of silence which is a R.R. characteristic. If we are to give the average customer, who does not use his cut-out, the advantage we expect to get from the new camshaft, it will be necessary to reduce the back pressure set up by the exhaust system. Ha/Rn.{Mr Robinson} | ||