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).
Improving vehicle performance and smoothness through engine, chassis, and body modifications.
| Identifier | ExFiles\Box 137\4\ scan0210 | |
| Date | 16th August 1931 guessed | |
| (5) and thick rubber top and bottom at the side, no other metal touching, you will get much better results than at present for all torque vibrations, - i.e. torque reaction, over-run and harmonic of crankshaft period. That if you tackle the flywheel you will be able to raise the 65 MPH. period to over 80. By the simplest expedient of lightening, and less overhang, with stiffer back plate flange and fixing. Then also something can be done with regard larger pins, and when convenient 4 small balance weights as large as master period will allow. These should be like oil on troubled waters to main bearings andc crankchamber deflections. I have said if only 30% they should be fitted. I have explained elsewhere how all these troubles either do not exist or can be more easily dealt with in the 12 cyl. Vee engine which we ought to push on with. The double top will do some good as it can avoid both the excessively high engine revs. and the very low ditto. It is more necessary for a 6 cyl. engine than for a 12 cyl. Would an Hispano help you to judge or find our imperfections. It has not double bearings and is firmly fixed in the frame and has a combined gearbox. I do not think for a moment P. 2. is worse than P. 1. except in the engine mounting, but P. 2. is generally the faster car. I have ignored all thought of engine mounting making a chassis which is too flexible for good steering as you have not mentioned this point in recent trials, and when you get the mounting you need for smoothness this feature can be criticised. Personally I believe there is more in road springs and less in frame stiffness than we imagined. Mr. Sidgreaves thinks double 28 HP. would be too large, heavy, and costly in tax. so that the size would probably be 3" X 4.5/8". I had hoped that with such an engine we could use the crankchamber to stiffen the frame because we should not need such flexible mounting, but something about the efficiency of vibration insulation of the present P.2. but I am now less hopeful because ordinary mechanical imperfections of balance might be found sufficient to vibrate some troublesome undamped feature. Everything about a body that it is possible to give a low period or damped construction should be carefully carried out - some of the steel bodies seem to be stiffened so tha | ||