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For 1990-2009 cars only

Engine Mechanical Specifications 4.3L

Application

Specification

Metric

English

General Data

  • Engine Type

V8

  • Displacement

4.3L

265 CID

  • Bore

94.89 mm

3.736 in

  • Stroke

76.20 mm

3.000 in

  • Compression Ratio

9.93:1

  • Firing Order

1-8-4-3-6-5-7-2

  • Spark Plug Type

AC41-943

  • Spark Plug Gap

1.24 mm

0.050 in

  1. Spark Plug Torque (Cylinder Head - New)

30 N·m

22 lb ft

  • Spark Plug Torque (Cylinder Head - All Subsequent Installations)

20 N·m

15 lb ft

  • Oil Pressure (Minimum Hot)

41.4 kPa at 1,000 engine RPM

124.1 kPa at 2,000 engine RPM

165.4 kPa at 4,000 engine RPM

6.0 psig at 1,000 engine RPM

18.0 psig at 2,000 engine RPM

24.0 psig at 4,000 engine RPM

  • Oil Filter Torque

20 N·m

15 lb ft

Cylinder Bore

  • Diameter

94.881-94.957 mm

3.7355-3.7385 in

  • Out-of-Round Production

0.02 mm (Maximum)

0.001 in (Maximum)

  • Out-of-Round Service Limit

0.05 mm (Maximum)

0.002 in (Maximum)

  • Taper Production Thrust Side

0.012 mm (Maximum)

0.0005 in (Maximum)

  • Taper Production Relief Side

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Taper Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

Piston

  • Piston Bore Clearance-Production

0.025-0.068 mm

0.0010-0.0027 in

  • Piston Bore Clearance-Service Limit

0.068 mm (Maximum)

0.0027 mm (Maximum)

Piston Rings

  • Piston Compression Ring Groove Clearance-Production Top

0.030-0.073 mm

0.0012-0.0029 in

  • Piston Compression Ring Groove Clearance-Production 2nd

0.030-0.073 mm

0.0012-0.0029 in

  • Piston Compression Ring Groove Clearance-Service Limit

0.107 mm (Maximum)

0.0042 in (Maximum)

  • Piston Compression Ring Gap-Production Top

0.25-0.40 mm

0.010-0.016 in

  • Piston Compression Ring Gap-Production 2nd

0.46-0.66 mm (Maximum)

0.018-0.026 in (Maximum)

  • Piston Compression Ring Gap-Service Limit

0.88  (Maximum)

0.035 in (Maximum)

  • Piston Oil Ring Groove Clearance-Production

0.051-0.17 mm

0.002-0.007 in

  • Piston Oil Ring Groove Clearance-Service Limit

0.20 mm (Maximum)

0.008 in (Maximum)

  • Piston Oil Ring Gap-Production

0.25-0.76 mm

0.010-0.030 in

  • Piston Oil Ring Gap-Service Limit

1.65 mm (Maximum)

0.065 in (Maximum)

Piston Pin

  • Diameter

23.545-23.548 mm

0.9270-0.9271 in

  • Clearance in Piston-Production

0.0120-0.0210 mm

0.0004-0.0008 in

  • Clearance in Piston-Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Fit in Connecting Rod

0.021-0.040 mm (Interference)

0.0008-0.0016 in (Interference)

Crankshaft

  • Crankshaft Journal-Diameter #1

62.192-62.207 mm

2.4485-2.4491 in

  • Crankshaft Journal-Diameter #2, #3, #4

62.192-62.207 mm

2.4485-2.4491 in

  • Crankshaft Journal-Diameter #5

62.192-62.207 mm

2.4485-2.4491 in

  • Crankshaft Journal Taper-Production #1, #2, #3, #4

0.005 mm (Maximum)

0.0002 in (Maximum)

Crankshaft Journal Taper-Production #5

0.007 mm (Maximum)

0.0003 mm (Maximum)

  • Crankshaft Journal Out-of-Round-Production

0.005 mm (Maximum)

0.0002 in (Maximum)

  • Crankshaft Journal Out-of-Round-Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Crankshaft Bearing Clearance-Production #1

0.020-0.051 mm

0.0008-0.0020 in

  • Crankshaft Bearing Clearance-Production #2, #3, #4

0.028-0.051 mm

0.0011-0.0020 in

  • Crankshaft Bearing Clearance-Production #5

0.043-0.081 mm

0.0017-0.0032 in

  • Crankshaft Bearing Clearance-Service Limit #1

0.025-0.038 mm

0.0010-0.0015 in

  • Crankshaft Bearing Clearance-Service Limit #2, #3, #4

0.025-0.064 mm

0.0010-0.025 in

  • Crankshaft Bearing Clearance-Service Limit #5

0.064-0.089 mm

0.0025-0.0035 in

  • Crankshaft End Play

0.05-0.20 mm

0.002-0.008 in

  • Crankshaft Runout (At Rear Flange)

0.038 mm

0.0015 in

Connecting Rod

  • Connecting Rod Journal Diameter

53.284-53.335 mm

2.0978-2.0998 in

  • Connecting Rod Journal Taper-Production

0.007 mm (Maximum)

0.0003 in (Maximum)

  • Connecting Rod Journal Taper-Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Connecting Rod Journal Out-of-Round-Production

0.007 mm (Maximum)

0.0003 in (Maximum)

  • Connecting Rod Journal Out-of-Round-Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Rod Bearing Clearance-Production

0.033-0.088 mm

0.0013-0.0035 in

  • Rod Bearing Clearance-Service Limit

0.025-0.076 mm

0.0010-0.0030 in

  • Rod Side Clearance

0.16-0.61 mm

0.006-0.024 in

Camshaft

  • Journal Diameter

47.440-47.490 mm

1.8677-1.8697 in

  • End Play

0.11-0.30 mm

0.004-0.012 in

  • Lobe Lift

±0.050 mm

±0.002 in

  • Lobe Lift Intake

7.02 mm

0.276 in

  • Lobe Lift Exhaust

7.25 mm

0.285 in

Valve System

  • Valve Lifter

Hydraulic

  • Valve Rocker Arm Ratio

1.50:1

  • Valve Lash

1 ±¼ turn from zero lash

  • Face Angle

45 degrees

  • Seat Angle (Cylinder Head)

46 degrees

  • Seat Runout (Cylinder Head)

0.05 mm (Maximum)

0.002 in (Maximum)

  • Seat Width Intake (Cylinder Head)

0.76-1.27 mm

0.030-0.050 in

  • Seat Width Exhaust (Cylinder Head)

1.52-2.03 mm

0.060-0.080 in

  • Stem Clearance Production Intake

0.025-0.069 mm

0.0010-0.0027 in

  • Stem Clearance Production Exhaust

0.025-0.069 mm

0.0010-0.0027 in

  • Stem Clearance Service Limit Intake

0.093 mm (Maximum)

0.0037 in (Maximum)

  • Stem Clearance Service Limit Exhaust

0.119 mm (Maximum)

0.0047 in (Maximum)

  • Valve Spring Free Length

51.3 mm

2.02 in

  • Valve Spring Pressure Closed

338-374 N at 43.2 mm

76-84 lb at 1.70 in

  • Valve Spring Pressure Open

832-903 N at 32.3 mm

187-203 lb at 1.27 in

  • Valve Spring Installed Height Intake

44.2 mm

1.74 in

  • Valve Spring Installed Height Exhaust

44.2 mm

1.74 in

  • Valve Lift Intake

10.52 mm

0.414 in

  • Valve Lift Exhaust

10.87 mm

0.428 in

  • Cylinder Head Intake Manifold Surface Flatness (measured within a 152.4 mm (6.00 in) area)

0.10 mm

0.004 in

  • Cylinder Head Deck Surface Flatness

0.10 mm

0.004 in

  • Cylinder Head Exhaust Manifold Surface Flatness (measured within a 152.4 mm (6.00 in) area)

0.10 mm

0.004 in

Engine Mechanical Specifications 5.7L

Application

Specification

Metric

English

General Data

  • Engine Type

V8

  • Displacement

5.7L

350 CID

  • Bore

101.60 mm

4.000 in

  • Stroke

88.39 mm

3.480 in

  • Compression Ratio

10.4:1

  • Firing Order

1-8-4-3-6-5-7-2

  • Spark Plug Type

AC41-943

  • Spark Plug Gap

1.24 mm

0.050 in

  1. Spark Plug Torque (Cylinder Head - New)

30 N·m

22 lb ft

  • Spark Plug Torque (Cylinder Head - All Subsequent Installations)

20 N·m

15 lb ft

  • Oil Pressure (Minimum Hot)

41.4 kPa at 1,000 engine RPM

124.1 kPa at 2,000 engine RPM

165.4 kPa at 4,000 engine RPM

6.0 psig at 1,000 engine RPM

18.0 psig at 2,000 engine RPM

24.0 psig at 4,000 engine RPM

  • Oil Filter Torque

20 N·m

15 lb ft

Cylinder Bore

  • Diameter

101.618-101.643 mm

4.0007-4.0017 in

  • Out-of-Round Production

0.02 mm (Maximum)

0.001 in (Maximum)

  • Out-of-Round Service Limit

0.05 mm (Maximum)

0.002 in (Maximum)

  • Taper Production Thrust Side

0.012 mm (Maximum)

0.0005 in (Maximum)

  • Taper Production Relief Side

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Taper Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

Piston

  • Piston Bore Clearance-Production

0.025-0.068 mm

0.0010-0.0027 in

  • Piston Bore Clearance-Service Limit

0.068 mm (Maximum)

0.0027 mm (Maximum)

Piston Rings

  • Piston Compression Ring Groove Clearance-Production Top

0.050-0.090 mm

0.0019-0.0035 in

  • Piston Compression Ring Groove Clearance-Production 2nd

0.050-0.090 mm

0.0019-0.0035 in

  • Piston Compression Ring Groove Clearance-Service Limit

0.107 mm (Maximum)

0.0042 in (Maximum)

  • Piston Compression Ring Gap-Production Top

0.25-0.40 mm

0.010-0.016 in

  • Piston Compression Ring Gap-Production 2nd

0.46-0.66 mm (Maximum)

0.018-0.026 in (Maximum)

  • Piston Compression Ring Gap-Service Limit

0.88  (Maximum)

0.035 in (Maximum)

  • Piston Oil Ring Groove Clearance-Production

0.051-0.17 mm

0.002-0.007 in

  • Piston Oil Ring Groove Clearance-Service Limit

0.20 mm (Maximum)

0.008 in (Maximum)

  • Piston Oil Ring Gap-Production

0.25-0.76 mm

0.010-0.030 in

  • Piston Oil Ring Gap-Service Limit

1.65 mm (Maximum)

0.065 in (Maximum)

Piston Pin

  • Diameter

23.545-23.548 mm

0.9270-0.9271 in

  • Clearance in Piston-Production

0.0120-0.0210 mm

0.0004-0.0008 in

  • Clearance in Piston-Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Fit in Connecting Rod

0.021-0.040 mm (Interference)

0.0008-0.0016 in (Interference)

Crankshaft

  • Crankshaft Journal-Diameter #1

62.189-62.212 mm

2.4484-2.4493 in

  • Crankshaft Journal-Diameter #2, #3, #4

62.182-62.205 mm

2.4481-2.4490 in

  • Crankshaft Journal-Diameter #5

62.177-62.199 mm

2.4479-2.4488 in

  • Crankshaft Journal Taper-Production

0.005 mm (Maximum)

0.0002 in (Maximum)

  • Crankshaft Journal Out-of-Round-Production

0.005 mm (Maximum)

0.0002 in (Maximum)

  • Crankshaft Journal Out-of-Round-Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Crankshaft Bearing Clearance-Production #1

0.017-0.053 mm

0.0007-0.0021 in

  • Crankshaft Bearing Clearance-Production #2, #3, #4

0.022-0.061 mm

0.0009-0.0024 in

  • Crankshaft Bearing Clearance-Production #5

0.025-0.069 mm

0.0010-0.0027 in

  • Crankshaft Bearing Clearance-Service Limit #1

0.025-0.051 mm

0.0010-0.0020 in

  • Crankshaft Bearing Clearance-Service Limit #2, #3, #4

0.025-0.064 mm

0.0010-0.025 in

  • Crankshaft Bearing Clearance-Service Limit #5

0.038-0.076 mm

0.0015-0.0030 in

  • Crankshaft End Play

0.050-0.20 mm

0.002-0.008 in

  • Crankshaft Runout (At Rear Flange)

0.038 mm

0.0015 in

Connecting Rod

  • Connecting Rod Journal Diameter

53.284-53.334 mm

2.0978-2.0998 in

  • Connecting Rod Journal Taper-Production

0.007 mm (Maximum)

0.0003 in (Maximum)

  • Connecting Rod Journal Taper-Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Connecting Rod Journal Out-of-Round-Production

0.007 mm (Maximum)

0.0003 in (Maximum)

  • Connecting Rod Journal Out-of-Round-Service Limit

0.025 mm (Maximum)

0.0010 in (Maximum)

  • Rod Bearing Clearance-Production

0.033-0.088 mm

0.0013-0.0035 in

  • Rod Bearing Clearance-Service Limit

0.025-0.076 mm

0.0010-0.0030 in

  • Rod Side Clearance

0.16-0.35 mm

0.006-0.024 in

Camshaft

  • Journal Diameter

47.440-47.490 mm

1.8677-1.8697 in

  • End Play

0.11-0.30 mm

0.004-0.012 in

  • Lobe Lift

±0.050 mm

±0.002 in

  • Lobe Lift Intake

7.02 mm

0.276 in

  • Lobe Lift Exhaust

7.25 mm

0.285 in

Valve System

  • Valve Lifter

Hydraulic

  • Valve Rocker Arm Ratio

1.50:1

  • Valve Lash

1 ±¼ turn from zero lash

  • Face Angle

45 degrees

  • Seat Angle (Cylinder Head)

46 degrees

  • Seat Runout (Cylinder Head)

0.05 mm (Maximum)

0.002 in (Maximum)

  • Seat Width Intake (Cylinder Head)

0.76-1.27 mm

0.030-0.050 in

  • Seat Width Exhaust (Cylinder Head)

1.52-2.03 mm

0.060-0.080 in

  • Stem Clearance Production Intake

0.025-0.069 mm

0.0010-0.0027 in

  • Stem Clearance Production Exhaust

0.025-0.069 mm

0.0010-0.0027 in

  • Stem Clearance Service Limit Intake

0.093 mm (Maximum)

0.0037 in (Maximum)

  • Stem Clearance Service Limit Exhaust

0.119 mm (Maximum)

0.0047 in (Maximum)

  • Valve Spring Free Length

51.3 mm

2.02 in

  • Valve Spring Pressure Closed

338-374 N at 43.2 mm

76-84 lb at 1.70 in

  • Valve Spring Pressure Open

832-903 N at 43.2 mm

187-203 lb at 1.27 in

  • Valve Spring Installed Height Intake

44.2 mm

1.74 in

  • Valve Spring Installed Height Exhaust

44.2 mm

1.74 in

  • Valve Lift Intake

10.52 mm

0.414 in

  • Valve Lift Exhaust

10.87 mm

0.428 in

  • Cylinder Head Intake Manifold Surface Flatness (measured within a 152.4 mm (6.00 in) area)

0.10 mm

0.004 in

  • Cylinder Head Deck Surface Flatness

0.102 mm

0.004 in

  • Cylinder Head Exhaust Manifold Surface Flatness (measured within a 152.4 mm (6.00 in) area)

0.10 mm

0.004 in