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3.1L (Gen 2) Specifications

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  • 3.1L (Gen 2) Specifications

    General Data: All dimensions are in millimeters

    Type

    60 degree V6

    Displacement

    3.1L

    RPO

    LH0

    Bore

    89.0

    Stroke

    84.0

    Deck Height

    224

    Compression Ratio

    8.8:1

    Firing Order

    1-2-3-4-5-6

    Oil Pressure

    69 kPa @500 RPM; 205-380 kPa @ 2000 RPM

    (10 psi @ 500 RPM; 30-55 psi @ 2000R RPM)

    Cylinder Bore:

    Diameter

    89.017-89.035

    Out of Round

    0.013 (Maximum)

    Taper - Thrust Side

    0.02 (Maximum)

    Piston:

    Clearance

    0.022-0.058

    Piston Ring:

    COMPRESSION

    Groove Clearance

    Top

    0.051-0.089

    Second

    0.051-0.089

    Gap

    Top

    0.18-0.41

    Second

    0.51-0.71

    OIL

    Groove Clearance

    0.2(Maximum)

    Gap

    0.25-0.76

    Piston Pin:

    Diameter

    22.992-22.997

    Clearance

    0.010-0.020

    Fit in Rod

    0.018-0.046

    Crankshaft:

    Main

    Journal

    Diameter

    67.241-67.265

    Taper

    0.005 (Maximum)

    Out Of Round

    0.005 (Maximum)

    Main Bearing Clearance

    0.032-0.077

    Crankshaft End Play

    0.06-0.21

    Crankpin

    Diameter

    50.758-50.784

    Taper

    0.005 (Maximum)

    Out of Round

    0.005 (Maximum)

    Rod Bearing Clearance

    0.028-0.086

    Rod Side Clearance

    0.18-0.44

    Camshaft:

    Lift

    Intake

    6.68

    Exhaust

    6.93

    Journal Diameter

    *

    Journals 1 & 4

    51.03-51.08

    Journals 2 & 3

    50.77-50.83

    Journal Clearance

    0.03-0.10

    Valve System:

    Lifter

    Hydraulic

    Rocker Arm Ratio

    1.50:1

    Valve Lash

    Intake

    1-1/2 Turns Down from Zero Lash

    Exhaust

    Face Angle (Intake & Exhaust)

    45 degrees

    Margin *
    Exhaust

    2.70

    Intake

    2.10

    Runout

    0.3

    Stem Clearance

    0.2-.0.53

    Valve Spring

    Free Length

    48.5

    Pressure

    N @ mm

    Closed

    391 @ 40

    Open

    867 @30

    Installed Height

    43

    Valve Spring

    Damper

    Free Length

    48.5

    Approx # of Coils

    4

    Fastener Tightening Specifications

    Item

    Nm

    Ft Lbs

    Camshaft Sprocket Bolt 24 18
    Connecting Rod Cap Nut 50 37
    Crankshaft Damper Bolt 103 76
    Cylinder Head Bolt (In Sequence) (apply thread sealant to bolts)
    First Pass 45 33
    Final Pass Add 90 degrees

    *Manifold Side*

    6 2 3 7

    5 1 4 8

    * Outer Side *

    Exhaust Manifold Bolt 28 21
    Flexplate/Flywheel Bolt 83 61
    Front Timing Cover Case Bolt
    Long 45 35
    Short 21 15
    Intake Manifold (In Sequence)
    First Pass 20 15
    Final Pass 33 24
    *
    Main Bearing Cap Bolt
    First Pass 50 37
    Final Pass Add 77 Degrees
    Oil Filter Adapter 39 29
    Oil Pan Rear Bolts 25 18
    Oil Pan Bolt and Nut (Except Rear 2) 6 7
    Oil Pump Bolt 41 30
    Rocker Arm Nut 27 20
    Rocker Arm Stud 25 18
    Belt Tensioner 54 40
    Throttle Body Bolts 24 18
    Timing Chain Damper Bolt 21 15
    Water Pump Pulley Bolt 20 15
    Water Pump To Block Bolt 24 18
    Water Pump To Front Cover Bolt 8 10
    Exhaust Crossover Pipe Nut 8 10
    Exhaust Heat Shield Nut 8 10
    Valve Cover Bolt 8 10
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