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 curve graph for Engine No. SS 15, showing brake horse power vs RPM for an exhaust heated hot-spot system.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan104 | |
| Date | 22th October 1929 | |
| POWER CURVE (EXHAUST HEATED HOT-SPOT) ENGINE No. SS{S. Smith} 15 STANDARD INDUCTION SYSTEM EXCEPT FOR HOT-SPOT CAR TYPE SILENCER HOT-SPOT EXHAUSTS INTO ATMOSPHERE BRAKE HORSE POWER STD. WATER HEATED HOT-SPOT HOT SPOT TEMP* *THESE TEMPERATURES REACH A HIGHER VALUE THAN OBTAINABLE ON THE ROAD, DUE TO LACK OF COOLING BY FAN AND ALSO DUE TO A GREATER CIRCULATION THRO' HOT-SPOT OCCASIONED BY EXHAUSTING DIRECTLY INTO ATMOSPHERE INSTEAD OF FISHTAIL PIPE R.P.M. OF ENGINE HOT-SPOT TEMPERATURE (CENTIGRADE) RM{William Robotham - Chief Engineer} 22.10-29 | ||