Cadillac V8 OHV gen. I 331 (1949)
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Specifications

Cadillac V8 OHV 331 genereation I, V8 (90o) cyl, 4 stroke, petrol engine
Introduced in 1949
Cadillac 331 OHV Technical information

Dimensions

Cylinders arrangement: V8 with 90ยบ included angle
Strokes: 4
Bore x Stroke:
96.8375 x 92.075 mm (3.8125" x 3.625")
Capacity: 5425.1 cc, 331ci

Construction materials

cast iron block 268.2 mm deck height, 115.9 mm (4.5625") bore spacing
steel head
steel crankshaft with 5 main bearings 63.5 mm (2.5") diameter, 57.1mm (2.249") big end bearing diameter
connecting rod distance center to center 168.3 mm

Cylinder-head

side camshaft in block with overhead valves (OHV). 2 valves per cylinder - 16 valves total

Aspiration

Natural

  • 2 x Carter WCD 722S two-barrel carburetor
  • 2 x Carter WCD 845S two-barrel carburetor
  • 2 x Rochester BB two-barrel Model 7004200 carburetor

Ignition

Spark Plug: AC
Firing Order: 18436572 (front to rear: Right bank 2-4-6-8, left bank 1-3-5-7)
1949: 6 volts
1951: 12 volts
negative ground

Cooling and lubrication

Water cooled
wet sump

Models used and Output

Year Model, Engine Induction Compression ratio Power Torque
1950 Allard J2 2 x Carter WCD 722S carb 7.5:1 158 HP / 118 kW @ 4000 rpm 423 Nm / 312 ft-lb @ 1800 rpm
1951 Allard J2X 1 x Carter WCD 845S two-barrel or
1 x Rochester BB 7004200 carb
8.25:1 210 @ 4150 rpm 330 Lbs.Ft @ 2700 rpm
1952 Allard J2X LM 2 x Rochester Carbs 9.0:1 250 HP @ 4600 rpm 345 ft-lb @ 2800 rpm
1953 Allard J2R 2 x Rochester Carbs 10.0:1 300 bhp / 224 KW HP @ 5000 rpm 508 Nm / 375 ft-lb @ 2800 rpm

Photos

1952_Cadillac_331-OHV_%7BV-8%7D_art.jpg Source
80311-500-0@2x.jpg?rev=3 Source
s-l300.jpg Source
Carter WCD 722S carburetor
CarterWCD-1950Cadillac-742S-400.jpg Source
Carter WCD 845S carburetor
s-l225.jpg Source
Rochester BB 7004200 flange kit
pinoffset.jpg

Service features

Year 1949 1951 1952
Normal Oil Pressure 35 Pounds
Spark Plug AC 48X AC 46-5 AC 44-5
Spark Plug gap 0.035" gap
Timing Mark "A" mark for premiurm fuel; "C" mark for regular fuel; location: Vib. Damper
Engine Idle Speed (rpm), Standard transmission 375 450 (in drive)
Engine Idle Speed (rpm), Automatic transmission 375 400 (in drive)
Cylinder Head Torque Lbs.Ft. 65-70
Compression Pressure & Cranking Speed 140 150 165
PISTON AND RING SPECIFICATIONS
Fitting Pistons with Scale Pistons removed from above Shim thickness: .002
Pounds on a Pull Scale 11
Ring End Gap (In tapered cylinder bores, fit rings in tightest portion of ring travel)
Compression Ring End Gap .007 .010
Oil Ring End Gap .007 .010
Compression Ring Clearance in Groove .0022-0035 .0017-.0035
Oil Ring Clearance in Groove .0015-.003 .0015-.003
Wristpin Diameter, Inch 1.000
VALVE SPECIFICATIONS
Operating Clearance, Intake / Exhaust 0 / 0
Valve Seat Angle, degrees 44
Valve Timing: (BTDC = before top dead center; ATDC = after top dead center)
Intake opens 15 BTDC 19 BTDC
Exhaust Closes 40 ATDC 30 ATDC
Valve Spring Pressure Pounds at Inches Length
Inner Spring 60 @ 1-11/16
Intake Valve Stem Clearance .001-.0025 .0005-.0025
Exhaust Valve Stem Clearance .0015-.0035 .001-.0025
ENGINE BEARING SPECIFICATIONS
Connecting Rod Bearings
Journal Diameter, Inches 2.2488-2.2493
Bearing Clearance, Inch .0005-.002
Rod End Play, Inch .008-.014
Rod Bolt Tension: Lbs.Ft. 40-45
Main Bearings
Journal Diameter, Inches 2.4990-2.4995
Bearing clearance .0008-.0025
Shaft End Play .001-.005 (Thrust on Rear Bearing)
Main Bolt Tension: Lbs.Ft. 90-100
CAPACITY DATA
Cooling System (Without heater) 18 quarts
Cooling System (With heater) 19 Series 60, 62, 75: 20-1/3 quarts
Series 75: 22-4/5 quarts
Fuel Tank 20 gallons
Engine Oil 5 quarts
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