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).
Performance of a Bentley car, specifically the gudgeon pins, brakes, and gaskets.
| Identifier | ExFiles\Box 82\1\ scan0130 | |
| Date | 12th April 1933 | |
| KC853A To Sg.{Arthur F. Sidgreaves - MD} from Hs.{Lord Ernest Hives - Chair} C. Wor.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} Hs.{Lord Ernest Hives - Chair}4/KT.12.4.33. BENTLEY CAR. Replying to Sg.{Arthur F. Sidgreaves - MD}5/Ell.4.33. We have received no report which gives any indication that the split rings holding the gudgeon pin are causing any trouble. You will see by GWH{George W. Hancock - Head Chateauroux}'s report after 12,000 miles that there is no sign of the split ring having fidgetted. Although we have used gudgeon pins with aluminium plugs in the end with success on standard cars, this is not evidence that they would be satisfactory in the Bentley. We are gradually accumulating a lot of experience from test bed running of the Bentley engine, and we do not think there is any doubt at present that the spring clip can be made satisfactory. Brakes. Rm.{William Robotham - Chief Engineer} drove the car a fast continental run of 2300 miles without adjusting the brakes, and Bn.{W.O. Bentley / Mr Barrington} drove it a further 1500 miles without adjusting the brakes. We have to weigh up very carefully the conditions under which the car is driven at Chateauroux before making any alterations. On the next car we are fitting an improved brake lining which we know will give us less wear. It will have to be realised that in the Bentley we cannot expect the same life as regard brakes as we have on the standard car. The power weight ratio of the Bentley is nearly double that of the 20/25 HP. That is the only way we get the performance. If we are going to keep on increasing the weight the car would become very uninteresting. We have got designs for using larger brake drums, but we are not satisfied that these are necessary. As regards your query with reference to the gasket, it will be remembered that the Bentley car running in France, was mostly made up, in the Expl. Dept., by parts available; the engines in that car is the one out of 16.G.IV. which R.{Sir Henry Royce} had at West WitteringHenry Royce's home town for nearly two years. That car was made up by us in order to show what the Bentley car would be like. At Chateauroux they had to use the gasket which was available. The maximum lap speed of the Bentley car before it went to France, with the cut-out open, was 88.5 mph. The lap speed at Brooklands is our recognised speed for cars, and we do not | ||