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).
Page detailing engine component specifications and performance test results for Cyclone and Conqueror engines.
| Identifier | ExFiles\Box 173\1\ img078 | |
| Date | 15th January 1934 guessed | |
| --2-- Hs.{Lord Ernest Hives - Chair} the valves equal in size: Cyclone .040 sq. in. Conqueror .024 sq. in. Balance Weights: They are fitting an appreciable amount of balance weight owing to cracked crankcases. Kelmit-Bearings: Used throughout the engine. No trouble. No light running high speed tests carried out for more than 1 minute. Magnesium: Bottom halves made in this material. Summary: The development of this engine is held up until they can get the exhaust valves to stand up on lead. Without lead they cannot get a fuel with an octane greater than 80. They have few production orders for Conquerors. B. Air Cooled Power They have just completed a type test on the Cyclone to the following schedule: Pound H.P. Hr. .65 Max. permissible fuel usually .55 - .60 50 hrs. Max. pwer (100%) 25 " 97% speed on prop. load 25 " 93% " " " " 71% Pow.. 25 " 89% " " " " 15 hrs. Sdle and 100% 10 hrs. 100% power and 110% speed developing 750 H.P. for 950 lbs. weight or 168 B.M.E.P. at 1900 R.P.M. with a fuel consumption of .6 lbs./B.H.P. Hr. 87 Octane fuel 3 c.c. lead. On the 1520 double row radial they have completed 50 hours at 770 B.H.P. and continued for a further 30 hrs. at 9/10 of this. The test was run at 2400 R.P.M. fuel as above. Exhaust Valves: The air cooled exhaust valves do not like lead, but as indicated above will pass an American type test, which is considerably stiffer than ours, running at 168 B.M.E.P. and 3 c.c.'s lead. The exhaust valves weigh over 1 lb. each, K.E. 965 type steel, are stellited, and have sodium cooled stems only. I saw the valves they had incipient guttering but no more. If they go to more lead or more power they expect to be in difficulty but so far are not. | ||