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).
Performance graph comparing manifold only and full exhaust systems on a Phantom II engine.
| Identifier | ExFiles\Box 179\2\ img007 | |
| Date | 30th November 1931 | |
| RM.{William Robotham - Chief Engineer} P.40 30/11/31 COMPARISON OF MANIFOLD ONLY. C.O OPEN & FULL EXHAUST SYSTEM P.II COMPLETE SHORT TYPE EXHAUST SYSTEM 1 1/4" CAMSHAFT TO F.B.23448 4.65 C/R STD. CYL HEAD. 1.9" VALVE THROAT MANIFOLD ONLY. R.R. TWIN CARBS. 1.4" DIA. CHOKES. C.O OPEN. COMPLETE P.II SHORT EXHAUST SYSTEM Valve Timing Diagram: EX 60, IN 55, 15, .013 CL'CE Axis Labels: Left Y-Axis: B.H.P. Right Y-Axis: B.M.E.P. LBS/D' X-Axis: R.P.M. Curve Labels: FULL EXHAUST SYSTEM EXHAUST BACK PR B.H.P C.O. Closed C.O. OPEN EXHAUST BACK PRESS. | ||