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Second Chance Garage

For the Classic Car
Restoration Enthusiast

Second Chance Garage

Second Chance Garage

For the Classic Car
Restoration Enthusiast

Second Chance Garage

Second Chance Garage

For the Classic Car Restoration Enthusiast

Second Chance Garage

ENGINE SPECS

1950 Oldsmobile 303 V8 Engine Specs

GENERAL SPECIFICATIONS

Model Designation: 88, 98

Wheel base: 88: 119-1/2; 98: 122

Valve Location: In Head

Bore and Stroke: 3-3/4 x 3-7/17

Piston displacement, Cubic Inches: 303.7

Compression ratio: 7.25

Maximum Brake Horsepower: 135 @ 3600 RPM

Maximum Torque Lbs.Ft. @ RPM: 263 @ 1800 RPM

Normal Oil Pressure Pounds: 40

TUNE UP SPECIFICATIONS (all models)

Spark Plug Make: AC 46-5

Spark Plug Gap, Inch: .030

Firing Order: 18736542 (left bank: 1-3-5-6; right bank: 2-4-6-8)

Timing Mark: between 2 balls or slot, location: pulley

Engine Idle Speed, RPM: Standard transmission: 425; w/automatic 375 (in drive)

Cylinder Head Torque Lbs.Ft.: 60-70

Compression Pressure & Cranking Speed: 120

Voltage & Polarity: 6 volts, negative ground

PISTON AND RING SPECIFICATIONS

Fitting Pistons with Scale: Pistons removed from above. Shim thickness: .0015

Pounds on a Pull Scale: 10 to 18

Ring End Gap: In tapered bores, fit rings in tightest portion of ring travel
Compression: Sealed Power: .008; Perfect Circle: .010
Oil: Sealed Power: .008; Perfect Circle: .010

Clearance in Groove: Compression: .001-003; Oil: .001-.0025

Wristpin Diameter, Inch: .9803-.9807

VALVE SPECIFICATIONS

Operating Clearance: Intake: 0Exhaust: 0

Valve Seat Angle, degrees: 45

Valve Timing: (BTDC = before top dead center; ATDC = after top dead center)
Intake opens: 13-1/2 BTDC
Exhaust Closes: 14-1/2 ATDC

Valve Spring Pressure Pounds at Inches Length: Inner Spring: 65 @ 1-3/4

Valve Stem Clearance: Intake: .002-.004;Exhaust: .0025-.0045

Clearance for Timing Intake: 0

ENGINE BEARING SPECIFICATIONS

Connecting Rod Bearings: Journal Diameter, Inches: 2.488-2.2498
Bearing Clearance, Inch: .0009-.0029
Rod End Play, Inch: .002-.011
Rod Bolt Tension: Lbs.Ft.: 45-50

Main Bearings: Journal Diameter, Inches: Nos. 1, 2, 3, 4: 2.498; No. 5: 2.623-2.624
Bearing clearance: For Rear Main: .002-.0035; others: .0005-.003
Shaft End Play: .004-.008(Thrust is taken at rear bearing)
Main Bolt Tension: Lbs.Ft.: Rear: 140 ft/lbs; all others: 100 ft.lbs

CAPACITY DATA

Cooling System: Without heater: 21-1/2 quarts
Without heater: 22-1/2 quarts

Fuel Tank: 18 gallons

Engine Oil: 5 quarts

Transmission: w/out overdrive: 3 pints; Automatic: 11 quarts

Rear Axle: 3-3/4 pints

DELCO-REMY DISTRIBUTOR SPECIFICATIONS

Distributor part number: 1110814 (distributor rotates counter-clockwise)

Cam Angle, degrees: 21-30

Breaker Point opening, Inch: .016

Condenser Capacity: .18-.23 Mfds.

Breaker Arm Spring Tension: 19-23 Oz.

Centrifugal Advance: (degrees at RPM of distributor)
Advance starts: 2 @ 400 RPM
Full Advance: 16 @ 1850 RPM
Inches of Vacuum to Start Plunger Movement: 6-1/2 - 8-1/2
Inches of Vacuum for Full Plunger Movement: 19-21
Maximum Vacuum Advance Dist., Degrees: 10

DELCO-REMY GENERATOR SPECIFICATIONS

Generator Number: 1102706, 1102707 (generator rotates clockwise, 6 volts, Negative Ground)

Generator output: 40 amps @ 2150 RPM

Brush Spring Tension: 28 oz.

Field Current at 6 Volts: 1.87-2.0

DELCO-REMY REGULATOR SPECIFICATIONS

Regulator Number: 1118300

Cutout Relay: Voltage to close points: 6.4
Reverse current to open points: 0-3
Armature Air Gap: .020

Voltage Regulator Setting: 7.3 volts

Current and Voltage Armature Air Gap: .075 inches

Current Regulator Setting: 42 amps

DELCO-REMY STARTING MOTOR SPECIFICATIONS

Part number: 1107956 (rotates clockwise)

Bush Spring Tension, Ounces: 24-28

No Load Test: 60 amps, 5.0 volts @ 6000 RPM

Torque Test: 600 Amps, 3.0 volts, Torque, Lbs.Ft.: 15

WHEEL ALIGNMENT SPECIFICATIONS

Caster, Degrees
Limits: -3/4 to 0
Desired: - 3/8

Camber, Degrees
Limits: -3/4 to +3/4
Desired: 0

Toe-In, Inches: 1/16 to 1/8

Toe-Out on Turns, Degrees: (If toe-out is incorrect, when other adjustments are correct, look for bent steering arms.)
Outer wheel: 20
Inner Wheel: 22-1/2 to 23-1/2

Kingpin Angle, or Steering Axis Degrees: (If king pin or spindle support angle are incorrect, but camber is correct, look for bent suspension arms or steering knuckle support) 4-1/2