1952 Pontiac 239 (102 hp) Inline Six Engine Specs

GENERAL SPECIFICATIONS

Year: 1952
Model Designation: Silver Streak 6 - 52-25 (with Hydramatic transmission)
Wheel Base: 120
Valve Location: In Block
Timing Mark Location: In Block
Bore & Stroke: 3-9/16 x 4
Piston Displacement, Cubic Inches: 239.2 Compression Ratio: 7.7
Maximum Brake HP @ RPM: 102 @ 3400
Maximum Torque Lbs. Ft. @ RPM: 189 @ 1400
Normal Oil Pressure Lbs: 35

TUNE UP SPECIFICATIONS

Disconnect vacuum line when using timing light to set timing.
Ground Polarity & Voltage: N-6
Spark Plug Type: A.C. 44-5
Spark Plug Gap, Inch: .025
Distributor:
Point Gap, Inch .022
Cam Angle Degrees: 31-37
Firing Order: 153624
Ignition Timing:
Timing Mark: When cranking engine first line to come under pointer on the vibration damper is for standard cylinder heads, the second line is for high compression heads, and the third line indicates top dead center.
Timing Mark Location: Damper
Idle Speed RPM in Neutral: 450 Cylinder Head Torque Ft. Lbs.: 60

VALVE SPECIFICATIONS

Running Clearance:
Int: .012H
Exh: .012H
Valve Seat Angle, Degrees: Intake 30 degrees exhaust 45 degrees.
Valve Timing (-BTDC: Before top dead center. ATDC: After top dead center.)
Intake Opens Deg. BTDC: 5
Exhaust Closes Deg. ATDC: 5
Valve Spring Pressure Lbs. at Inches Length: 56 @ 1 29/32
Stem Clearance:
Int: Guides taper .001" to the inch and when started in the guide the valve should fall through of its own weight.
Exh: Guides taper .001" to the inch and when started in the guide the valve should fall through of its own weight.
Stem Diameter, Std.
Int: .3105
Exh: .3105

COOLING SYSTEM & CAPACITY DATA

Cooling System Data
Quarts No Heater: 18
Quarts With Heater: 27 1/2
Fuel Tank Gals: 17 1/2
Engine Oil
Refill Quarts: (-Add one quart with filter change): 5
Summer Grade: 20
Winter Grade: 10W
Transmissions
Hydramatic: 12 qts. Hydramatic fluid
Rear Axle Pints: 3 1/4

PISTON, PINS, RINGS, CRANKSHAFT & BEARINGS

Ring End Gap (-Fit rings in tapered bores for clearance given in tightest portion of ring travel)
Comp: .009
Oil: .009
Rod Bearings
Shaft Diameter: 2.1237-2.1247
Bearing Clearance: .0001-.0021
Main Bearings Shaft Diameter: No. 1, 2.4982-2.4992, No. 2, 2.5294-2.5304, No. 3, 2.5919-2.5929, rear, 2.6232-2.6242
Bearing Clearance: .0003-.0023
Thrust on Bear. No.: 3
Shaft End Play: .003-.008

REAR AXLE SPECIFICATIONS

Ring, Gear & Pinion Backlash, Inch: .003-.012
Drive Pinion Adjustment: Shim
Drive Pinion Bearing Adjustment: Nut
Axle Shaft End Play, Inch: .000.008

WHEEL ALIGNMENT SPECIFICATIONS

Preferred Caster, Degrees: -3/4

Preferred Camber, Degrees: Zero

Toe-In, Inches: 1/32 Kingpin Angle, Degrees: (-Incorrect kingpin angle with correct camber indicates bent suspension arms or steering knuckle support): 5