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 trials of car 27-EX with increased compression and 2 S.U. carburettors.
| Identifier | ExFiles\Box 19\1\ Scan188 | |
| Date | 2nd March 1932 | |
| 87120. To Hs.{Lord Ernest Hives - Chair} from Sg.{Arthur F. Sidgreaves - MD} Copy to R.{Sir Henry Royce} Wor.{Arthur Wormald - General Works Manager} BY.{R.W. Bailey - Chief Engineer} [crossed out: E.{Mr Elliott - Chief Engineer} C.] Sg{Arthur F. Sidgreaves - MD}10/E2.3.32 re 27-EX with Increased Compression, 2 S.U. Carburetters etc. This car was returned to you on Monday afternoon. Experience of its running has been had by C., Cx.{Major Len W. Cox - Advertising Manager}, PN.{Mr Northey} and myself, so that we could get not only an idea of its definite performance relatively to our standard trials Continental car No.31-GX, but also from the point of view of Rolls-Royce qualities. Although there were sundry features of interest on the car, such as the easy-change semi-epicyclic on all gears, we were chiefly concerned with whether we should be justified in pushing forward the revolutionary use of a pair of S.U. carburetters instead of waiting for the development of the R.R. carburetters which are now in the Experimental Dept. by reason of any outstanding improvement in road performance. Speaking generally, we did not find that there was any serious amount of loss of Rolls-Royceness, such as poor slow-running, or greatly marked fuss and roar when using these S.U. carburetters, although of course the latter condition was generally found to be excessive compared with the sounds made by the standard R.R. carburetter when the throttle is fully open. Our impression of performance was greatly based upon the relative speeds of our Continental Trials Car 31-GX. This car was first used by way of comparison last week at Brooklands when PN.{Mr Northey} made a number of acceleration tests up to 70 m.p.h. when it was found that with the difference of an overall weight of 3 cwt in favour of 31-GX there was no difference in acceleration until a speed of 50 m.p.h. had been passed, when at 70 m.p.h. 27-EX had worked its way ahead by about three car lengths. Subsequently we made a number of tests on the arterial roads near Welwyn with the two cars, in which the approximate difference in weight of 3 cwt was equalised by carrying sufficient passengers in 31-GX, whilst PN.{Mr Northey} alone drove 27-EX. During these tests we were able to note at various speeds the sort of difference a customer would observe between such a | ||