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).
Weight savings and additions for a Bentley car model.
| Identifier | ExFiles\Box 88\3\ scan0001 | |
| Date | 22th April 1933 | |
| To E.{Mr Elliott - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. Da.{Bernard Day - Chassis Design} By.{R.W. Bailey - Chief Engineer} c. Ev.{Ivan Evernden - coachwork} BENTLEY WEIGHTS. The first Bentley car complete weighed 30 cwt. 2 qrs. We decided to try and get the car weight down to 30 cwt. and actually eliminated 60 lbs. of the weight in the following manner :- Lightened flywheel - Weight saving 30 lbs. Substituting a narrower matrix and thermostat for the original matrix and radiator shutters - Weight saving 24 lbs. Exhaust system - Weight saving 6 lbs. After incorporating these modifications, the 2nd. Bentley car weighed 30 Cwt. 3 qrs complete. Analysing the increase in weight we get the following results :- Larger petrol tank - 2 lbs. 2 galls. petrol - 14 lbs. 40/50 dynamo instead of 25 HP. - 9 lbs. P.100 headlamps instead of P.80. - 8 lbs. Two horns instead of one - 2½ lbs. Five discs for wheels - 31 lbs. 6 ozs. CAV. Voltage Regulator - 2 lbs. Total 68 lbs. 14 ozs. To this we can add a certain unknown amount for the increase in engine dimensions due to reducing the dynamo speed. Certain items are unavoidable, but others appear to us to be unnecessary, at any rate for our model cars. The argument that the customer will insist on other items later is another matter. We have to demonstrate the performance, and as it is the first time that R.R. have produced an acknowledged Sports Car, we must concentrate on the power/wt. ratio. We think that the P.100 headlamps, both from a point of windage and weight, are unnecessarily large. We also think that disc wheels are undesirable. | ||