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).
Comparing car performance based on weight and engine capacity for the 'SS', 20 HP, Phantom, and Chrysler models.
| Identifier | ExFiles\Box 107\4\ scan0092 | |
| Date | 13th April 1929 | |
| +4538 To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} PN.{Mr Northey} c. to EP.{G. Eric Platford - Chief Quality Engineer} Hs{Lord Ernest Hives - Chair}1/LG13.4.29. CAR PERFORMANCE. +4012 +7840 We are quite in agreement, that if we could reduce the weights to the proportions you mention, there will be no complaints about the performance. We think however that one or two of the weights you mention need correction. We have now had five complete 'SS{S. Smith}' cars, some of them were fitted with the largest bodies we have ever fitted to Phantom cars. The max. weight of the 'SS{S. Smith}' car we should not expect to exceed is 43 cwts. This is ready for the road, without passengers and luggage. Therefore if the 20 HP. is to be 60% of the weight, the complete car should not exceed 25½ cwts. Actually the cubic capacity of the 20 HP. is 41% that of the Phantom and the weight taken as 34 cwts. and 50 cwts. for the Phantom, the 20HP. is 68%. If it were possible to reduce the weight of the 20 HP. car to 23½ cwts. we do not think there would be any complaints about the performance because at this figure the capacity per ton per mile would be equal to the Chrysler. Tests have shewn that cars with equal capacity per ton per mile give approx. the same acceleration. We attach a chart giving particulars and on actual road tests we find that the Phantom and the Chrysler have approx. the same acceleration up to 50 m.p.h. Hs.{Lord Ernest Hives - Chair} | ||