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).
Suspension design, weight distribution, and handling improvements for 20HP and 40/50 models.
| Identifier | WestWitteringFiles\R\January1928-March1928\ 17 | |
| Date | 14th January 1928 | |
| HS.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} } FROM R.{Sir Henry Royce} DA.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} } C to BI RG{Mr Rowledge} C SC. 20HP. & 40/50 SUSPENSION. x5410 Referring to HS{Lord Ernest Hives - Chair}/RM.{William Robotham - Chief Engineer}20/12/27., the points mentioned are now well agreed upon but we must be careful what we recommend. For instance I am particularly anxious not to use front bumpers especially, because (1) they increase the weight on the steering wheels (front road), (2) they increase the difficulties of shunting and getting through traffic, and (3) increase the weight generally - ugly, brutal things. With both our cars the thing within our practical reach is to increase the damping to more than what we consider best - i.e. let it be too much rather than too little. It should all be done in the hydraulics, even if we make them larger and generally more robust. Naturally we should move tools, batteries, etc, back. Lighten everything near the centre of the car and body. Especially does it suggest light folding seats and central glass and winding gear. It is very good to get the passengers forward, as in Sports saloon: don't therefore condemn short bodies. In conjunction with the front axle control we have lately shortened the front lever (to 12" or 12 1/2" I think it is). Is this to be standard? because we can bear much damping on the front. The early "twenties" were very bad cars to pitch: this was entirely due to insufficient dampers I believe. A car with the weight forward and aft beyond the wheels ought to be dangerous from control, skidding, etc, so that we should not bring the condition too near your ideal riding car. I conclude we should get most benefit by lightening the front so that the front springs are naturally less rigid: let us therefore get even the smallest weight possible from the front wheels (i.e. can we still further reduce the clutch and flywheel?) Any top heavy car I have always cursed, so that the roof must be as low and light as possible. Everywhere we must save weight except behind the centre of the back axle: low down, unsprung weight in this position can be looked upon as advantageous, and is the only place that weight can be added with advantage. The centre of gravity must come down (nearer the ground), and must go back: weight between the wheels must be reduced to the minimum. (Our experience on the rough roads here suggest that front buffer clearance must be increased by half at least.) (1) | ||