Review of the 25 HP model's position and proposals for performance improvements and developments.
| Identifier | ExFiles\Box 5a\1\ 01-page263 | |
| Date | 25th January 1931 | |
| Sg. {Arthur F. Sidgreaves - MD} From Hy {Tom Haldenby - Plant Engineer} /Hs. {Lord Ernest Hives - Chair} C. Wot. A. {Mr Adams} 85770 Hs. {Lord Ernest Hives - Chair} 1/W.25.13.31. X.5770. X.5123. 25 HP. We think it is useful to review the position of the 25 HP. and the possible developments. Commencing the last as in 'T' series we expect to standardise the 25 HP. car as represented by 16-G4 - which has just completed 10,000 miles tests in France. Compared with the present 25 HP. car we are selling, this car will have an increased performance, Synchro mesh gear-box, and more durable engine because of having balance weights fitted. There are also numerous detail improvements. This car will be a definite step forward, but it would be a mistake for anyone to imagine that this car will have any better performance than the average car of the same rating. If it is proposed to market a 25 HP. Continental car we think that this car should have an improved performance over the standard 25 HP. or else we shall only be in the position as we are with the present Phantom II Continental model, and that is we shall find the standard car faster in some cases than the car we are selling as a Continental model. Fortunately, it is possible to increase the performance with very few extra parts. Our proposals are contained in Hs {Lord Ernest Hives - Chair} /Rep/434. Briefly, they consist of a modified N.R. carburetter, higher compression ratio, and fitting exhaust cut-out. When these modifications are made, we think then we shall have reached the limit of what can be done with the present 'China(Experimental Engine)' engine. As you are aware, it has already been agreed that we shall send 16-G4 car to France again in order to prove out the modified exhaust system and the modifications which are necessary to the synchro-mesh gearbox as it will be used on production. We would like you to agree that when 16-G4, goes back to France it should have the modifications which we are suggesting for the Continental 25 HP. carried out on the engine. This would then give us an opportunity of proving these parts out. Another modification would be to run the car with the 18" dia. road wheel, and the higher axle ratio as fitted to 20-G4. Hs. {Lord Ernest Hives - Chair} | ||
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).