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).
Graph analysing losses to the exhaust system for a Phantom II short type silencer.
| Identifier | WestWitteringFiles\W\September1931-November1931\ Scan069 | |
| Date | 2nd November 1931 guessed | |
| LOSSES TO EXHAUST SYSTEM P.II. RM.{William Robotham - Chief Engineer} P.35 ANALYSIS OF COMPLETE P.II. SHORT TYPE SILENCER 4.6 C/R 108° MASKED VALVE CAMSHAFT TWIN CARBS 1.4 DIA. THROAT B.H.P. B.M.E.P. R.P.M. ① OPEN EXHAUST ② MANIFOLD ONLY ③ MANIFOLD AND DOWNTAKE ④ MANIFOLD DOWNTAKE AND EXPANSION BOX THE B.H.P. RISES BY 3 WHEN THE INTERMEDIATE PIPE IS ADDED TO CURVE 4. THIS EXPLAINS WHY CURVE 4 IS MUCH THE SAME AS CURVE 2 ON RM.{William Robotham - Chief Engineer} P.33 | ||