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 three different front exhaust expansion chamber configurations on a Bentley B.2 Unit.
| Identifier | ExFiles\Box 86\3\ scan0080 | |
| Date | 30th January 1935 | |
| B.V.75 COMPARISON OF FRONT EXPANSION CHAMBERS (BENTLEY) B.2. UNIT SPECIFICATION :- R.H.C./CP 7/EP{G. Eric Platford - Chief Quality Engineer} 30-1-35 AEROLITE PISTONS H.1 (17.0 OZS) E.B. 2050 CYLINDER HEAD 7.0:1 COMPRESSION RATIO 1.500 DIA. INLET VALVES, 1.300 DIA. EXHAUST VALVES. STANDARD INDUCTION SYSTEM WITH No AIR SILENCER. ① STANDARD FRONT EXPANSION Box ② FRONT EXPANSION Box TO HS.{Lord Ernest Hives - Chair} 1585 ③ OPEN EXHAUST STANDARD SYSTEM. HS.{Lord Ernest Hives - Chair} 1585 SYSTEM. MAIN EXPANSION CHAMBER NOT FITTED IN EITHER CASE VALVE TIMING (.010 CLEARANCE) T.D.C. EXH 83° 31° INL 50° 70° B.H.P. R.P.M. EXHAUST BACK PRESS. (INS.Hg) B.M.E.P.(LB/SQ.") | ||