V6 Engines

General Engine Block
Pistons and Rings Cylinder Heads
Crankshaft and Flywheel Camshaft and Valve Train
Oil Pump Gear End Clearance Oversize & Undersize Component Code Letter Definition
Torque Specifications

Type90 V6
Displacement225 cu in
Bore and Stroke3.750 x 3.400 in
Compression Ratio
Federal 9.0 : 1
California 7.4 : 1
Oil Pressure33 psi at 2400 rpm
Cylinder Numbering(front-to-rear)
Right Bank 2-4-6
Left Bank 1-3-5

Engine Block
Cylinder Bore
Taper Limit0.005 in
Out-of-Round Limit0.003 in
Piston-to-Cylinder Bore Clearance
Standard 0.001 in
Service Limit 0.0015 in

Pistons and Rings
Piston Ring Side Clearance
Top Ring0.002 in
2nd Ring0.003 in
Oil Ring0.0015 in
Service Limit
Top Ring0.0035 in
2nd Ring0.005 in
Oil Ring0.0085 in
Piston Ring End Gap
Compression Rings0.010 in
Oil Ring0.015 in
Service Limit
Compression Rings0.020 in
Oil Ring0.035 in
Piston Pin Diameter0.9334 to 0.9397
Piston Pin-to-Piston Clearance
Standard0.004 in
Service Limit0.0017 in
Piston Pin-to-Connecting Rod Clearance0.0007 to 0.0017 in

Cylinder Heads
Valve Seat Angle 45
Valve Seat Width
Standard 1/16 in
Service Limit 5/64 in
Valve Stem Diameter
Intake 0.3415 to 0.3427
Top0.3402 to 0.3412
Bottom0.3397 to 0.3407
Valve Head Diameter
Intake 1.625 in
Exhaust 1.3750 in
Valve Stem-to-Guide Clearance
Intake0.0012 to 0.0032 in
Top0.0015 to 0.0035 in
Bottom0.002 to 0.004 in
Valve Margin Width 1/32 in minimum
Valve Stem Installed Height1.925 in above cylinder head
Valve Spring Pressure1.640 in at 59 to 64 lb.
1.260 in at 168 lb

Crankshaft and Flywheel
Main Journal
Diameter2.4995 in
Taper Limit0.002 to 0.0023 in
Out of Round Limit0.0015 in
Main Bearing Oil Clearance
Standard0.0005 in
Service Limit0.0021 in
Connecting Rod Journal
Diameter2.000 in
Taper Limit0.003 in
Out-of-Round0.0015 in
Connecting Rod Bearing Oil Clearance
Standard0.020 in
Service Limit0.0023 in
Connecting Rod End Play0.005 to 0.0012 in
total for two rods
Crankshaft End Play0.004 to 0.008 in
Flywheel Clutch Face Runout Limit0.0015 in

Camshaft and Valve Train
Bearing Journal Diameter
Number 11.755 to 1.756 in
Number 21.725 to 1.726 in
Number 31.695 to 1.696 in
Number 41.665 to 1.666 in
Bearing Oil Clearance
Standard0.0015 in
Service Limit0.0040 in
Lifter TypeHydraulic
Lifter-to-Bore Clearance
Standard0.0015 in
Service Limit0.0030 in
Rocker Arm-to-Shaft Clearance0.0017 to 0.0032 in

Oil Pump Gear End Clearance0.0023 to 0.0058 in

Oversize and Undersize Component Code Letter Definition
Code Letter
AMain & Connecting Rod Bearings0.010 in undersize
BPistons0.010 in oversize
ABCombination of A & B
RShort Block
SService engine

Torque SpecificationsFT-LbsNm
Main Bearing Cap Bolts80 to 110129 to 162
Connecting Rod Cap Nuts30 to 4041 to 54
Cylinder Head Bolts65 to 8588 to 109
Fan Pulley-to-Vibration Damper Bolts18 to 2525 to 34
Flywheel-to-Crankshaft Bolts50 to 6568 to 88
Vibration Damper Bolts140190
Oil Pan Bolts10 to 1614 to 22
Oil Pan Drain Plug30 to 4041 to 54
Oil Pump Cover-to-Timing Chain Cover8 to 1211 to 17
Oil Pump Pressure Relief Valve25 to 3034 to 41
Oil Screen Housing6 to 98 to 12
Oil Pan Baffle9 to 1312 to 17
Oil Gallery Plugs20 to 3027 to 41
Oil Filter10 to 1514 to 20
Timing Chain Cover Bolts25 to 3334 to 45
Water Pump Bolts6 to 88 to 11
Fan Driven Pulley Bolts17 to 2323 to 32
Thermostat Housing Bolts17 to 2323 to 32
Intake Manifold Bolts45 to 5561 to 75
Exhaust Manifold Bolts15 to 2020 to 27
Carburetor-to-Intake Manifold Bolts10 to 1514 to 20
Fuel Pump Bolts17 to 2323 to 32
Engine Mount-to-Block Bolts50 to 7568 to 102
Fuel Pump Eccentric &
Timing Chain Sprocket-to-Camshaft Bolt
40 to 5554 to 75
Rocker Arm Cover Bolts3 to 54 to 7
Rocker Arm Shaft Bracket Bolts25 to 3534 to 48
Alternator Bracket-to-Cylinder Head Bolts30 to 4041 to 54
Alternator Pivot Bolt30 to 4041 to 54
Alternator Bracket-to-Timing Chain Cover Bolt18 to 2524 to 34
Starter Motor Bolts30 to 4041 to 54
Starter Motor Brace9 to 1312 to 17
Distributor Hold-Down Clamp Bolts10 to 1514 to 20
Spark Plugs25 to 3534 to 48
Bellhousing-to-Block Bolts30 to 4041 to 54
Timing Chain Damper-to-Block Bolts6 to 98 to 12
Movable Timing Chain Damper Bolt10 to 1514 to 20