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 various experimental exhaust manifolds against a standard manifold and open exhausts on a 20 HP engine.
| Identifier | WestWitteringFiles\R\2December1927-February1928\ Scan112 | |
| Date | 17th January 1928 | |
| 20 HP EXPERIMENTAL EXHAUST MANIFOLDS. TESTS MADE ON 20 H.P. ENGINE COMPN RATIO 5.45/1. STD. CYL. HEAD & VALVES. LONG DURATION CAMSHAFT. ZENITH T.D. CARBURETTER (1). B.H.P. R.P.M. B.M.E.P. lbs/sq" OPEN EXHAUSTS SCH 935. SCH 936 STANDARD MANIFOLD. SCH. 934. Aeh 17/1/28 | ||