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).
Power comparison table for an EB. 615 head fitted to a standard engine with an open exhaust.
| Identifier | ExFiles\Box 86\1\ scan0190 | |
| Date | 20th March 1936 guessed | |
| POWER COMPARISION (Open Exhaust) EB. 615 head fitted to a standard engine | R.P.M. | B.M.E.P. | C B.H.P. | |---|---|---| | 4500 | 75.6 | 96.2 | | 4250 | 86.8 | 104.4 | | 4000 | 93.7 | 106.2 | | 3750 | 100.5 | 106.6 | | 3500 | 107.4 | 106.3 | | 3000 | 114.2 | 97.1 | | 2500 | 118.8 | 84.0 | | 2000 | 120.4 | 68.1 | | 1500 | 113.3 | 50.3 | | 1000 | 113.2 | 32 | | 750 | 109.5 | 23.8 | | ||