Engine Mechanical Specifications. Pontiac Grand Prix 2002

For 1990-2009 cars only

Makes 🢒 Pontiac 🢒 2002 🢒 Grand Prix 🢒 Engine 🢒 Engine Mechanical - 3.1L 🢒 Engine Mechanical Specifications

Application	Specification
Application	Metric	English
General Data
Engine Type	60° V-6
Displacement	3.1L	191 cu in
RPO - VIN Code	LG8 - J
Bore	89 mm	3.50 in
Stroke	84 mm	3.31 in
Compression Ratio	9.6:1
Firing Order	1-2-3-4-5-6
Oil Pressure	103 kPa	15 psi @ 1100 RPM
Block
Camshaft Bearing Bore Diameter - ID	47.516-47.541 mm	1.871-1.872 in
Camshaft Bearing Bore Diameter - Front and Rear	51.03-51.08 mm	2.009-2.011 in
Camshaft Bearing Bore Diameter - Middle #2, #3	50.77-50.82 mm	1.999-2.001 in
Crankshaft Main Bearing Bore Diameter	72.1535-72.1695 mm	2.8407-2.8413 in
Crankshaft Main Bearing Bore Out-of-Round	0.008 mm	0.0003 in
Cylinder Bore Diameter - Production	89.016-89.034 mm	3.5046-3.5053 in
Cylinder Bore Diameter - Service	89.016-89.042 mm	3.5046-3.5056 in
Cylinder Bore Out-of-Round - Diametral - Production	0.020 mm	0.0008 in
Cylinder Bore Out-of-Round - Diametral - Service	0.025 mm	0.001 in
Cylinder Bore Taper - Production	0.020 mm	0.0008 in
Cylinder Bore Taper - Service	0.025 mm	0.001 in
Cylinder Head Deck Height	224 mm	8.819 in
Cylinder Head Deck Surface Flatness	0.05 mm per 152 mm	0.002 in per 6 in
Valve Lifter Bore Diameter	21.417-21.455 mm	0.843-0.845 in
Piston
Diameter-Gaged on the skirt 12 mm (0.47 in) below the centerline of the piston pin bore	88.981-89.009 mm	3.5029-3.5040 in
Clearance	0.07-0.053 mm	0.0013-0.0027 in
Pin Bore	23.006-23.013 mm	0.9057-0.9060 in
Piston Ring
Top Groove Side Clearance	0.04-0.086 mm	0.002-0.0033 in
Second Groove Side Clearance	0.04-0.09 mm	0.002-0.0035 in
Top Ring Gap	0.15-0.36 mm	0.006-0.014 in
Second Ring Gap	0.5-0.71 mm	0.0197-0.0280 in
Oil Ring Groove Clearance	0.046-0.201 mm	0.008 in
Gap with segment at 89.0 mm (3.50 in)	0.25-1.27 mm	0.0098-0.05 in
Piston Pin
Diameter	22.9915-22.9964 mm	0.9052-0.9054 in
Clearance In Piston	0.0096-0.0215 mm	0.0004-0.0008 in
Fit In Rod	(-0.0469)-(0.017) mm (press fit)	0.0006-0.0018 in
Crankshaft
Main Journal Diameter	67.239-67.257 mm	2.6473-2.6483 in
Main Journal Taper	0.005 mm	0.0002 in
Out Of Round	0.005 mm	0.0002 in
Flange Runout-Max	0.04 mm	0.0016 in
Cylinder Block Main Bearing Bore Diameter	72.155-72.168 mm	2.8407-2.8412 in
Crankshaft Main Bearing Inside Diameter	67.289-67.316 mm	2.6492-2.6502 in
Main Bearing Clearance - except number 3	0.019-0.064 mm	0.0008-0.0025 in
Main Thrust Bearing Clearance - number 3	0.032-0.077 mm	0.0012-0.0030 in
Crankshaft End Play	0.060-0.210 mm	0.0024-0.0083 in
Crankshaft Flange Runout-Max	0.04 mm	0.0016 in
Connecting Rod
Connecting Rod Bearing Journal Diameter	50.768-50.784 mm	1.9987-1.9994 in
Connecting Rod Bearing Journal Taper	0.005 mm	0.0002 in
Connecting Rod Bearing Journal Out Of Round	0.005 mm	0.0002 in
Connecting Rod Bearing Bore Diameter	53.962-53.984 mm	2.124-2.125 in
Connecting Rod Inside Bearing Diameter	50.812-50.850 mm	2.000-2.002 in
Connecting Rod Bearing Journal Clearance	0.018-0.062 mm	0.0007-0.0024 in
Connecting Rod Side Clearance	0.18-0.44 mm	0.007-0.017 in
Camshaft
Lobe Lift - Intake and Exhaust	6.9263 mm	0.2727 in
Journal Diameter	47.45-47.48 mm	1.868-1.869 in
Camshaft Bearing Bore Diameter-Front and Rear	51.03-51.08 mm	2.009-2.011 in
Camshaft Bearing Bore Diameter-Middle #2 and #3	50.77-50.82 mm	1.999-2.001 in
Camshaft Bearing Inside Diameter	47.523-47.549 mm	1.871-1.872 in
Journal Clearance	0.026-0.101 mm	0.001-0.0039 in
Journal Runout-Max	0.025 mm	0.001 in
Cylinder Head
Combustion Chamber Depth - at Measurement Point	2.2 mm	0.087 in
Surface Finish - Maximum	2.8 RA
Surface Flatness - Block Deck	0.08 mm per 152 mm	0.003 in per 6 in
Surface Flatness - Exhaust Manifold Deck	0.1 mm	0.004 in
Surface Flatness - Intake Manifold Deck	0.1 mm	0.004 in
Valve Guide Bore - Exhaust	8.01 mm	0.315 in
Valve Guide Bore - Intake	8.01 mm	0.315 in
Valve Guide Installed Height	16.6 mm	0.654 in
Valve System
Roller Lifter	Hydraulic
Rocker Arm Ratio	1.60:1
Valve Face Angle	45°
Seat Angle	46°
Valve Seat Runout	0.025 mm	0.001 in
Seat Width-Intake	1.55-1.80 mm	0.061-0.071 in
Seat Width-Exhaust	1.70-2.0 mm	0.067-0.079 in
Valve Margin - Minimum Intake	2.10 mm	0.083 in
Valve Margin - Minimum Exhaust	2.70 mm	0.106 in
Valve Stem Clearance	0.026-0.068 mm	0.0010-0.0027 in
Valve Spring
Valve Springs Free Length	48.5 mm	1.89 in
Valve Springs Load - Closed	320 N @ 43.2 mm	75 lb @ 1.701 in
Valve Springs Load - Open	1036 N @ 32 mm	230 lb @ 1.260 in
Installed Height Intake-Exhaust	43.2 mm	1.701 in
Approx. # or coils	6.55
Oil Pump
Gear Lash	0.094-0.195 mm	0.0037-0.0077 in
Gear Pocket Depth	30.52-30.58 mm	1.202-1.204 in
Gear Pocket Diameter	38.176-38.226 mm	1.503-1.505 in
Oil Pump Gear
Length	30.45-30.48 mm	1.199-1.200 in
Diameter	38.05-38.10 mm	1.498-1.500 in
Side Clearance	0.038-0.088 mm	0.001-0.003 in
End Clearance	0.040-0.125 mm	0.002-0.005 in
Valve to Bore Clearance	0.038-0.089 mm	0.0015-0.0035 in