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).
Special oil consumption tests for production chassis.
| Identifier | ExFiles\Box 144\3\ scan0209 | |
| Date | 10th May 1937 | |
| PIII 1230 10.5.37 3-BT{Capt. J. S. Burt - Engineer}-109 PRODUCTION CHASSIS - SPECIAL OIL CONSUMPTION TESTS 490 m.p.g. .0027 Valve clearance. No grummits. No drains. 558 m.p.g. With drains - 14% improvement 725 m.p.g. Drains and Screens to prevent oil dropping on the upper part of valve springs. Close fitting valves gave very varying results ranging from 500 to 1000 m.p.g. depending on how and where chassis driven. Drains give a better figure of merit with close clearance valves i.e. 25% Fitting all improvements i.e. 1 Drains 2. Screens 3. Filling up slots in valve wedges 4 Close clearance valves gives 1120 m.p.g. on track 1393 " on road. Now doing a traffic run in Nottingham. 957 MPG Average figure for number of new chassis with close clearance valves is 730 m.p.g. If chassis given extra run of 200 miles on Dyno. @ 40 m.p.h. 3/4 lead Oil consumption improves by 150 to 200 m.p.g. Drains return oil to crankcase at rate of 1 gallon in 5 mins | ||