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Brooklands test results for a 12 G IV Close Coupled Four Seater car, comparing performance with different configurations.


Identifier  ExFiles\Box 181\M9\  img013
Date  14th August 1931
  
R.M. 28
12 G IV BROOKLANDS TEST 14/8/31
CLOSE COUPLED FOUR SEATER WT. 32.25 CWT
TYRES 6" FORT DUNLOPS 19" RIMS. 60 MPH = 3000 R.P.M.
AXLE RATIO 11 X 50

CONDITION OF CAR AND UNIT    LAP TIME    LAP SPEED

1) 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 MPH

2) AS 1 BUT S.U. CARB    2 MIN 26.4 SEC    67.57 MPH

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 63.7 M.P.H

STAMPED:
ROLLS-ROYCE LTD.
PRINT ROOM
17 AUG 31
  
  
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).


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