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 analysis of a 'V' series car, detailing carburation, maximum speed, and tractive resistance with comparisons to Phantom and Silver Ghost models.
Identifier | ExFiles\Box 24\5\ Scan096 | |
Date | 4th July 1925 guessed | |
-2- had this 'V' series car weighed only 2.15 cwts. We admit that even this is not as good as we anticipated having reagrd to the increase in M.E.P. There appeared to be a slightly weak spot in the carburation between 25 and 30 m.p.h. It will be noticed that this can be detected on the curve. The test was carried out accelerating straight up the scale without altering the mixture control. The point where the acceleration of the car reaches zero may be taken as the max. speed. From this graph it would appear to be 71.5 m.p.h. confirming graph 1. The readings for acceleration were naturally carried out on the same straights as those for tractive resistance. It would therefore appear that 71.5 m.p.h. would have been the mean max. speed on the straights. It should be observed that all the Phantom readings in these tests were taken with the hood and side curtains up and cut-out closed. The former precaution was taken to ensure easy manipulation of the Chronograph at high speeds. Both items would tend to adversley affect the car performance when compared with that previously given for the Silver Ghost. GRAPH 1V. This gives the measured mean tractive resistance curve for the car in lbs/ton. In plotting this curve allowance has been made for the K.E. of the rotating parts of the car when making the test. Curve A.{Mr Adams} is calculated from the top gear acceleration curve in graph lll., and the H.P. to drive the car Graph l. curve C. rotating parts have again contd :- | ||