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).
Test report on an overdrive gear for car 36-EX, detailing performance, fuel consumption, and potential overheating issues.
Identifier | ExFiles\Box 96\3\ scan0172 | |
Date | 20th February 1937 | |
Copy of letter received from "W" - On Board R.M.S.Queen Mary. To Sg.{Arthur F. Sidgreaves - MD} and Hs.{Lord Ernest Hives - Chair} c. Rm.{William Robotham - Chief Engineer} Da.{Bernard Day - Chassis Design} Hdy.{William Hardy} Rm{William Robotham - Chief Engineer}/Wst.Fm/FD.{Frank Dodd - Bodies} Re 36-EX. The results of my run on 36-EX last Sunday using the overdrive gear as much as possible show considerable improvement in petrol consumption without much loss of performance. Outward journey 120 miles in 2.5 hours 48 m.p.h. average - 13.8 miles per gallon consumption. Return journey at 37 m.p.h. average speed - 15 miles per gallon consumption. Total mileage for trip 247.5, and overall consumption 14.5 m.p.g. Maximum speed recorded on three occasions 95 m.p.h. against 97 for standard ratio. After 20 miles all out there was a smell apparently of hot oil in the car which might have been from the gearbox heating up. It would be worth while investigating this. When I originally suggested testing the overdrive gear in this way by converting a gearbox it was with a view to testing the gear ratio effect rather than considering it for a permanent scheme. With 36-EX as now running we have to realise that all the power is being handled twice over, and there are heavy end thrusts on ball bearings being carried for prolonged periods. Whether this is sufficient to overheat the oil can be tried. With the epicyclic overdrive, only a small percentage of the power is being handled by the gears, and this scheme | ||