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 comparing power losses in various exhaust systems against engine RPM.
| Identifier | ExFiles\Box 2\10\ 10-page26 | |
| Date | 4th October 1932 | |
| COMPARISON OF POWER LOSSES IN EX. SYSTEMS AS PER SKETCH H.S. 722 FREE SYSTEM E.100625 OTHER SYSTEM E.100464 IMPROVED HEAD E.100520 RH.{R. Hollingworth} PR.{Percy H. Rose} 30 6.23 C/R INLET VALVE 1.125 THROAT TWO S.U. CARBS. LODGE SHORT REACH PLUGS FORMS E.100361/2 T.D.E. REMOVED B.H.P. B.M.E.P R.P.M 75 M.P.H. A.10.72 Valve Timing Diagram: T.D.C. 8 10&1/2 Ex. .013 IN 39 40 Table: LOSS TO EXHAUST SYSTEM AT 4500 RPM OLD SYSTEM | NEW SYSTEM COMPLETE SYSTEM | 14.0 | 5.4 FISHTAIL REMOVED | 11.8 | 3.2 SILENCER REMOVED | 7.6 | 1.3 Legend: ① OPEN EXHAUST ② MANIFOLD & DOWNTAKE TO MAIN SILENCER FITTED. ③ As ② SILENCER FITTED ④ As ③ FISHTAIL FITTED COMPLETE SYSTEM ⑤ OLD SYSTEM EXP BOX E.100464 | ||