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Specification sheet for a White 12-cylinder horizontally opposed bus engine.


Identifier  ExFiles\Box 134\1\  scan0172
Date  2nd December 1939 guessed
  
WHITE 12 CYLINDER HORIZONTALLY OPPOSED BUS ENGINE

No of cylinders 12
Bore & Stroke 4¼ x 4¼
Piston displacement 681 cu: in:
Max: BHP‡ 210 @ 3000 RPM
Compression ratio 5.88 to 1
Max: torque 500 lbs at 1200 RPM
Weight without carburetter or ignition 2200 lbs

OVERALL DIMENSIONS
Width 38½"
Height 21¼"
Length 69½"

Valve DIMENSIONS
Inlet Exhaust
Max: head dia; 1.88 1.75
Min: port dia; 1.62 1.62
Lift .381 .381
Stem dia; .401 .401
Seat angle 30° 45°

PISTON DIMENSIONS
Length 4.40
Gudgeon pin 1.18 dia x 3.62 long
Weight (bushed alum alloy piston complete with pin and five rings) 44 ozs

CONNECTING RODS
Length (centre to centre) 8 1/32
Weight (with bush and cap) 51.5 oz

CRANKSHAFT
7 main bearings (balance weights used)
Main bearing dia: and length Front 2.87 x 2.18
Rear 2.87 x 2.50
Crank pin dia: and length 2.43 x 3.00
Side by side Con-rods.
TAS {T. Allan Swinden} /
  
  
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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