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 B.M.E.P. versus Piston Speed for various engines, with tables for valve timings, compression ratios, fuel, and engine specifications.
| Identifier | ExFiles\Box 144\4\ scan0076 | |
| Date | 19th April 1940 guessed | |
| B.M.E.P. S.183 DATA ① ASPIN 4.125 BORE 6" STROKE ② ASPIN 2.913 BORE 3.189 STROKE ③ RUDGE 3.346 BORE 3.464 STROKE ④ R.R 3.5 BORE 4.5 STROKE NORMAL CAR ENGINE ⑤ R.R 3.5 BORE 4.5 STROKE WITH SIX AMAL CARBS. NORMAL CAR ENGINE TUNED FOR RACING VALVE TIMINGS I.O. I.C. E.O. E.C. ① 5 BT{Capt. J. S. Burt - Engineer} 50 AB 35 BB 6 AT ② 20 BT{Capt. J. S. Burt - Engineer} 50 AB 55 BB 25 AT ③ 4° BT{Capt. J. S. Burt - Engineer} 50 AB 50 BB 7 AT ④ 2° BT{Capt. J. S. Burt - Engineer} 28 AB 51 BB 7 AT C/R ① 13.6:1 ③ 8:1 ④ 6.25:1 FUEL ① 65% POOL 35% BENZOL (73 OCT ALLEGED) ② 65% POOL 35% BENZOL (73 OCT ALLEGED) PISTON SPEED (FT/MIN) CORRESPONDING R.P.M. FOR R.R. ENGINES (4.500" STROKE) | ||