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 data from a Brooklands test comparing different car configurations and components.
| Identifier | Morton\M9\ img013 | |
| Date | 14th August 1931 | |
| RM.{William Robotham - Chief Engineer} 28 12 G IV BROOKLANDS TEST 14/8/31 CLOSE COUPLED FOUR SEATER WT. 32.25 CWT AXLE RATIO 11x50 TYRES 6" FORT DUNLOPS 19 RIMS. 60 M.P.H. = 3000 R.P.M. CONDITION OF CAR AND UNIT | Lap Time | Lap Speed 1. VALVE SPRINGS CAR IN STANDARD T SERIES CONDITION BUT WITH STRONGER VALVE SPRINGS WHICH SHOULD HAVE NO EFFECT AT THIS SPEED | 2 MIN 31.4 SEC | 65.78 M.P.H. 2. AS 1 BUT S.U. CARB | 2 MIN 26.4 SEC | 67.57 M.P.H 3. ENGINE GIVING 80 B.H.P. AS IN CURVE R.M. 27. STD CARB. C.O. CLOSED P II EX. SYSTEM | 2 MIN 17 SEC | 72.49 4. AS 3 BUT C.O. OPEN | 2 MIN 15.6 SEC | 73.45 5. ENGINE GIVING 89 B.H.P. AS IN CURVE R.M.27. S.U. CARB. C.O. CLOSED | 2 MIN 12.4 SEC | 75.23 6. AS 5 BUT C.O. OPEN | 2 MIN 10 SEC | 76.62 AIR TEMP 19° C TOP WATER TEMP PLAIN BONNET 82° C LOUVRED " 74° C PETROL CONS. 160 MILES DERBY - BROOKLANDS R.R. CARB 21 M.P.G. S.U. CARB. 20.0 M.P.G. 19 G IV 10,000 MILES CAR LAP SPEED 65.7 M.P.H. STAMP: ROLLS-ROYCE LTD. PRINT ROOM 17 AUG 31 | ||