GM 3.4L LA1 (3400) Specifications

Application	Specification
	Metric	English
General Data
Engine Type	60° V-6
Displacement	3.4L	204 cu in
RPO (VIN Code)	LA1 (E)
Bore	92 mm	3.62 in
Stroke	84 mm	3.31 in
Deck Height	224 mm	8.818 in
Compression Ratio	9.6:1
Firing Order	1-2-3-4-5-6
Oil Pressure - Warm	103 kPa	15 psi @ 1100 RPM
Cylinder Bore
Diameter	92.019-92.037 mm	3.6228-3.6235 in
Out Of Round Maximum	0.007 mm	0.0003 in
Taper -- Thrust Side Maximum	0.010 mm	0.0004 in
Piston
Diameter-Gaged on the skirt 13 mm (0.51 in) below the centerline of the piston pin bore	91.970-91.988 mm	3.6209-3.6216 in
Clearance	0.032-0.068 mm	0.0013-0.0027 in
Pin Bore	23.006-23.013 mm	0.9057-0.9060 in
Piston Ring
Top Groove Side Clearance	0.04-0.075 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	0.48-0.74 mm	0.0197-0.0280 in
Oil Ring Groove Clearance	0.48-0.20 mm	0.008 in
Gap with segment at 92.0 mm (3.62 in)	0.25-0.75 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 - Max	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	0.019-0.064 mm	0.0008-0.0025 in
Main Thrust Bearing Clearance	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
Rod Bearing Journal Diameter	50.768-50.784 mm	1.9987-1.9994 in
Rod Bearing Journal Taper - Max	0.005 mm	0.0002 in
Rod Bearing Journal Out Of Round - Max	0.005 mm	0.0002 in
Rod Bearing Bore Diameter	53.962-53.984 mm	2.124-2.125 in
Rod Inside Bearing Diameter	50.812-50.850 mm	2.000-2.002 in
Rod Bearing Journal Clearance	0.018-0.062 mm	0.0007-0.0024 in
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
Valve System
Roller Lifter	Hydraulic
Rocker Arm Ratio	1.60:1
Valve Face Angle	45°
Seat Angle	46°
Valve Seat Runout	0.050 mm	0.002 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
Cylinder Head CC	28.6cc
Piston CC	28.6cc
Head Gasket Bore	3.750"
Head Gasket Thickness	.060"
Piston Deck Height	-.020"

Torque Specifications For The LA1 and LG8

Application	Specification
	Metric	English
Accelerator Control Cable Bracket Bolt/Nut	10 N·m	89 lb in
Camshaft Position Sensor Bolt	10 N·m	89 lb in
Camshaft Sprocket Bolt	140 N·m	103 lb ft
Camshaft Thrust Plate Screw	10 N·m	89 lb in
Connecting Rod Bearing Cap Nut	20 N·m + 75°	15 lb ft + 75°
Coolant Drain Plug	19 N·m	14 lb ft
Coolant Temperature Sensor	23 N·m	17 lb ft
Crankshaft Balancer Bolt	103 N·m	76 lb ft
Crankshaft Main Bearing Cap Bolt/Stud	50 N·m +77°	37 lb ft + 77°
Crankshaft Oil Deflector Nut	25 N·m	18 lb ft
Crankshaft Position Sensor Bolt -- Front Cover	10 N·m	89 lb in
Crankshaft Position Sensor Stud -- Side of Engine Block	11 N·m	98 lb in
Crankshaft Position Sensor Wiring Bracket Bolt	27 N·m	20 lb ft
Cylinder Head Bolt	60 N·m + 95°	44 lb ft + 95°
Drive Belt Shield Bolt	10 N·m	89 lb in
Drive Belt Tensioner Bolt	50 N·m	37 lb ft
EGR Valve to EGR Valve Pipe Bolt	25 N·m	18 lb ft
EGR Valve Adapter Pipe to Exhaust Manifold Nut	25 N·m	18 lb ft
Engine Flywheel Bolt	71 N·m	52 lb ft
Engine Front Cover Bolt -- Large	55 N·m	41 lb ft
Engine Front Cover Bolt -- Medium	47 N·m	35 lb ft
Engine Front Cover Bolt -- Small	21 N·m	15 lb ft
Engine Mount Bracket Bolt	58 N·m	43 lb ft
Engine Mount Lower Nut	43 N·m	32 lb ft
Engine Mount Strut and Lift Bracket Bolt -- Engine Left Rear	70 N·m	52 lb ft
Engine Mount Strut Bolt/Nut	48 N·m	35 lb ft
Engine Mount Strut Bracket Bolt -- Upper Radiator Support	28 N·m	21 lb ft
Engine Mount Strut Bracket Bolt -- Vehicle Right Side	50 N·m	37 lb ft
Engine Mount Upper Nut	47 N·m	35 lb ft
Engine Oil Pressure Indicator Switch	13 N·m	115 lb in
Engine Wiring Harness Bracket Bolt	13 N·m	115 lb in
Exhaust Crossover Pipe Heat Shield Bolt	10 N·m	89 lb in
Exhaust Crossover Pipe Nut/Stud	25 N·m	18 lb ft
Exhaust Manifold Heat Shield Bolt	10 N·m	89 lb in
Exhaust Manifold Nut	16 N·m	12 lb ft
Exhaust Manifold Stud	18 N·m	13 lb ft
Fuel Feed Pipe to Fuel Injector Rail Nut	17 N·m	13 lb ft
Fuel Injector Rail Bolt	10 N·m	89 lb in
Fuel Pipe Bracket Bolt/Stud	50 N·m	37 lb ft
Fuel Pipe Clip Bolt	8 N·m	71 lb in
Fuel Return Pipe to Fuel Injector Rail Nut	17 N·m	13 lb ft
Generator Bracket and Front Engine Lift Hook Bolt	50 N·m	37 lb ft
Heated Oxygen Sensor	42 N·m	31 lb ft
Heater Inlet Pipe Nut	25 N·m	18 lb ft
Ignition Coil Bracket Bolt/Nut/Stud	25 N·m	18 lb ft
Intake Manifold Coolant Pipe Bolt	10 N·m	89 lb in
Knock Sensor	19 N·m	14 lb ft
Lower Intake Manifold Bolt - Center
· First Pass	7 N·m	62 lb in
· Final Pass	13 N·m	115 lb in
Lower Intake Manifold Bolt - Corner
· First Pass	13 N·m	115 lb in
· Final Pass	25 N·m	18 lb ft
MAP Sensor Bolt	5 N·m	44 lb in
Oil Cooler Connector	50 N·m	37 lb ft
Oil Cooler Hose Fitting	19 N·m	14 lb ft
Oil Cooler Pipe Bracket Bolt	10 N·m	89 lb in
Oil Filter	13 N·m	115 lb in
Oil Filter Bypass Hole Plug	19 N·m	14 lb ft
Oil Filter Fitting	39 N·m	29 lb ft
Oil Gallery Plug -- 1/4 inch	19 N·m	14 lb ft
Oil Gallery Plug -- 3/8 inch	33 N·m	24 lb ft
Oil Level Indicator Tube Stud	25 N·m	18 lb ft
Oil Level Sensor Bolt	10 N·m	89 lb in
Oil Pan Bolt	25 N·m	18 lb ft
Oil Pan Drain Plug	25 N·m	18 lb ft
Oil Pan Side Bolt	50 N·m	37 lb ft
Oil Pump Cover Bolt	10 N·m	89 lb in
Oil Pump Drive Clamp Bolt	36 N·m	27 lb ft
Oil Pump Mounting Bolt	41 N·m	30 lb ft
Spark Plug
· Spark Plug - Initial Installation	20 N·m	15 lb ft
· Spark Plug - Reinstallation	15 N·m	11 lb ft
Thermostat Bypass Pipe to Cylinder Head Nut	25 N·m	18 lb ft
Thermostat Bypass Pipe to Engine Front Cover Bolt	12 N·m	106 lb in
Thermostat Bypass Pipe to Throttle Body Nut	25 N·m	18 lb ft
Throttle Body Bolt/Stud	25 N·m	18 lb ft
Timing Chain Dampener Bolt	21 N·m	15 lb ft
Upper Intake Manifold Bolt/Stud	25 N·m	18 lb ft
Valve Lifter Guide Bolt	10 N·m	89 lb in
Valve Rocker Arm Bolt	19 N·m + 30°	14 lb ft+ 30°
Valve Rocker Arm Cover Bolt	10 N·m	89 lb in
Water Outlet Bolt	25 N·m	18 lb ft
Water Pump Bolt	10 N·m	89 lb in
Water Pump Pulley Bolt	25 N·m	18 lb ft