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).
Road test report on a car with independent front wheel suspension, detailing performance and suggesting modifications.
| Identifier | ExFiles\Box 154\1\ scan0112 | |
| Date | 30th January 1934 | |
| X3873 To Mr. from Da.{Bernard Day - Chassis Design} La.{L. A. Archer}3/HP.30.1.34. c.Sgr.Wor.{Arthur Wormald - General Works Manager} Hs.{Lord Ernest Hives - Chair} Hsy. By.{R.W. Bailey - Chief Engineer} Independent Front Wheel Suspension. --------------------------------- I had this car out last week-end and did a good run over a great variety of roads. The rear damping had been reduced to 60 lbs. so the suspension was very flexible both front and back. Decending a hill the car always crashed on the rear buffers at the bottom though there were only two people up. In spite of this flexibility the car seemed surprisingly controllable at speed. Over a good road the ride seemed extremely good. Over a not very good road there was a fair amount of pitching, probably due to the stiff buffer springs at the front coming into play rather sooner, and more violently than was necessary. I confirmed the effect noticed by Experimental Department, that striking an obstacle of some size rounding a curve produced a violent reaction the front suspension being then on the stiff buffer springs. The rating of both the main and buffer springs is based on the Lancia, taking the comparative weight of the cars and the different systems into account. We showed a diagram comparing the two cars when the scheme was first produced. It would now appear desirable to reduce the rate, at anyrate of the upward buffer and we suggest doing this by inserting another spring having approximately twice the rating of the main spring. This might come into operation a little earlier than the present buffer, the final buffer coming into play just before the stop and being of less rating than now. We will make a diagram showing how this compares with the system as now arranged. We think the rebound buffer might also be reduced in rating and another stage introduced as we think can easily be done. The Rolls-Royce scheme has an advantage that variable rating springs are easy to arrange. At moderate speeds over bad roads the car seemed to ride well. On a bad or indifferent road the steering joggled | ||