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Study of theoretical and actual fuel economy improvements for the Phantom model.


Identifier  WestWitteringFiles\N\2October1925-December1925\  Scan159
Date  18th November 1925
  
No. 4

FUEL ECONOMY POSSIBILITIES PHANTOM

THEORETICAL IDEAL

FACTOR TO BE ELIMINATED.
MAX. POSSIBLE IMPROVEMENT IN M.P.G.

A. {Mr Adams} ROLLING & WIND RESISTANCE. TYRE POWER TRANSMISSION LOSSES. - 35%

B. ENGINE FRICTION & PUMPING LOSSES. - 30%

OIL CHURNING LOSSES IN GEAR BOX. & BACK AXLE. - 8%

IMPROVEMENTS ACTUALLY AFFECTED

FACTOR ELIMINATED.
IMPROVEMENT M.P.G.

HIGH GEARED AXLE
RATIO RAISED FROM 3.47 TO 3.06.
11.5%

HARD TYRES.
PRESS RAISED FROM 25 TO 60 LBS/□".
10%

COOLING WATER TEMP.
RAISED FROM 70°C. TO 95°C.
8%

MAX. ECONOMY MIXTURE SETTING.
2 NOTCHES WEAK.
7%

EXTRA IGNITION ADVANCE.
FROM 20° TO 50° B.T.D.C.
4%

ROAD SPEED
ALL TESTS
20 M.P.H.

STAMP: ROLLS-ROYCE, LIMITED PRINT ROOM 18 NOV 1925 DERBY
  
  
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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