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).
List of modifications to engine components and the schedule and results of subsequent performance tests.
| Identifier | ExFiles\Box 179b\3\ img277 | |
| Date | 21th February 1933 | |
| -2- He/Yng.1/W.21.2.3. Cont'd.{John DeLooze - Company Secretary} Cylinders to LOP.E.39940. DES.1613-16-17-26-53 & 1768. - Raised floor type incorporating integral induction manifold, strengthened cyl. bolts, improved water space round exhaust ports, venturi type valve seats and spring loaded gland type cylinder liners. Carburetter to LOP.E.39707. DES.1642. - Improved type. Supercharger to LOP.E.9980. DES. 1664-1675-1740-1742. -(Gear ratio 8.823/1) modified to suit altered dynamo drive, also rotating guide vanes. Dynamo Drive to LOP.E.40217. DES.1675-1704. - Final drive housed in B.side engine rear bearer foot. Automatic Boost Control to LOP.E.40318. DES.1730. - Latest type regarded as standard for Kestrel production. In addition several proved and lightly-stressed assemblies incorporated "lightened" components. SCHEDULE AND RESULTS OF TESTS. (1) Rating test giving fully corrected powers at various altitudes at constant international speed of 2600 RPM. From this curve it will be seen that 604 BHP. was attained at an altitude of 12,000 ft. maintaining a rated boost pressure of plus 1 1/4 lbs/sq.in. (32.98" Hg. abs.) See curve 374 F.{Mr Friese} appended. The engine rating was therefore determined as :- Rated Altitude 12,000ft. Rated Alt. Power 600 BHP. at International speed 2600 R.P.M. Rated Boost Pressure plus 1 1/4 lbs/sq.in. (2) Rated altitude power curve taken at 12,000 ft. altitude conditions, from 3000 down to 2200 R.P.M. See curve 375F. appended. (3) Consumption loop to determine the normal mixture control position running at Rated Boost pressure plus 1 1/4 lb/sq.in. and at International speed 2600 R.P.M. See curve 306F. appended. | ||