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).
Standardization of axle ratios for the 40/50 HP model to improve acceleration in response to increasing traffic density.
| Identifier | ExFiles\Box 66\4\ scan0361 | |
| Date | 14th November 1927 | |
| S/W HS.{Lord Ernest Hives - Chair} X8350 BJ. Copy to:- C. Sg.{Arthur F. Sidgreaves - MD} PN.{Mr Northey} Whr.{Mr Wheeler} Hs.{Lord Ernest Hives - Chair} CWB15/GM/14.11.27. Re: AXLE RATIO, 40/50 H.P. With reference to Pt7/FM.11.10.27 attached, I agree entirely with Pt. on this matter. For other reasons we have already agreed to supply all chassis for America with a 14/52 back axle ratio and in view of Pt's observations here I consider we should standardise the same axle ratio for Australia. I consider also that the question of the most suitable axle ratio for this country needs re-considering, as in view of the rapidly growing increase of traffic density, particularly in and near the large towns, acceleration is becoming more and more the most important factor and the maximum top speed is becoming comparatively unimportant providing such speeds as are readily possible with the Phantom with a 14/52 axle ratio are obtainable. America has already found this out and, I believe in the first place, owing to the conditions which probably exist today in which Australia the conditions there have very rapidly changed to those of extreme traffic density in which acceleration means everything and hence we find that all the American cars are much lower geared than our own, and further, in these conditions put up an apparently superior performance. I suggest that conditions in England are rapidly approaching those of America and that if we are to maintain our place we must provide improved acceleration on top gear and that therefore instead of having a 15/52 standard with exceptions of 14/52 we should have a 14/52 standard with exceptions of 15/52. I know that this involves slightly increased fussiness in the engine, but this matter should be worked on so that in a reasonable time we shall be able to deliver a car with the lower gear ratio which is equally as free from fussiness as our present standard. CWB. | ||