Engine Mechanical Specifications. Pontiac Firebird 1998

For 1990-2009 cars only

Makes 🢒 Pontiac 🢒 1998 🢒 Firebird 🢒 Engine 🢒 Engine Mechanical - 3.8L 🢒 Engine Mechanical Specifications

Application	Specification
Application	Metric	English
General Data
Engine Type	90° V-6
Displacement	231 cu in
Liter (VIN)	3.8L (K)
RPO	L36
Bore	96.52 mm	3.8 in
Stroke	86.36 mm	3.4 in
Compression Ratio	9.4:1
Firing Order	1-6-5-4-3-2
Lubrication System
Oil Capacity with Oil Filter Change	4.25 L	4.5 qt
Oil Capacity without Oil Filter Change	3.75 L	4 qt
Oil Pressure @ Operating Temperature (1850 RPM) Using 10W-30 Oil	414 kPa	60 psi min
Oil Filter Type	Throw Away Element and Can
Gear Pocket Depth	11.71-11.75 mm	0.461-0.4625 in
Gear Pocket Diameter	89.10-89.20 mm	3.508-3.512 in
Inner Gear Tip Clearance	0.152 mm	0.006 in
Outer Gear Diameter Clearance	0.203-0.381 mm	0.008-0.015 in
End Clearance	0.025-0.089 mm	0.001-0.0035 in
Valve-to-Bore Clearance	0.038-0.076 mm	0.0015-0.003 in
Type of Lubrication
Main Bearings	Pressure
Connecting Rods	Pressure
Piston Pins	Splash
Balance Shaft Bearing - Front	Splash
Balance Shaft Bushing - Rear	Pressure
Camshaft Bearings	Pressure
Timing Chain	Splash
Cylinder Walls	Splash
Oil Pump Type	Gerotor
Oil Pressure Sending Unit	Electrical
Oil Intake	Stationary
Oil Filter System	Full Flow
Cylinder Bore
Diameter	96.5 mm	3.8 in
Out-Of-Round Maximum	0.0254 mm	0.001 in
Taper	0.0254 mm	0.001 in
Piston
Clearance (39 mm from Top of Piston)	0.010-0.051 mm	0.0004-0.0020 in
Piston Ring Groove Depth
Top Compression	4.019-4.146 mm	0.158-0.163 in
2nd Compression	4.214-4.341 mm	0.0166-0.171 in
Oil Control	3.814-3.941 mm	0.150-0.155 in
Piston Ring End Gap
Top Compression	0.305-0.559 mm	0.012-0.022 in
2nd Compression	0.762-1.016 mm	0.030-0.040 in
Oil Control	0.254-0.762 mm	0.010-0.030 in
Piston Ring Side Clearance
Top Compression	0.033-0.079 mm	0.0013-0.0031 in
2nd Compression	0.033-0.079 mm	0.0013-0.0031 in
Oil Control	0.023-0.201 mm	0.0009-0.0079 in
Piston Ring Width
Top Compression	1.176-1.197 mm	0.0463-0.0471
2nd Compression	1.476-1.497 mm	0.0581-0.0589
Oil Control	1.854-2.007 mm	0.073-0.079
Piston Pin
Diameter	21.9950-22.0000 mm	0.8659-0.8661 in
Clearance in Piston	0.0020-0.0130 mm	0.00008-0.00051 in
Fit-In-Rod (Clearance)	0.0066-0.0217 mm	0.0003-0.0009 in
Crankshaft
Main Journal Diameter-All	63.470-63.495 mm	2.4988-2.4998 in
Rod Journal Diameter-All	57.1170-57.1475 mm	2.2487-2.2499 in
Main Journal Taper-Maximum	0.0076 mm	0.0003 in
Rod Journal Taper-Maximum	0.0076 mm	0.0003 in
Main Journal Out-of-Round-Maximum	0.0076 mm	0.0003 in
Rod Journal Out-of-Round-Maximum	0.0076 mm	0.0003 in
Main Bearing To Journal Clearance 1	0.0178-0.0406 mm	0.0007-0.0016 in
Main Bearing To Journal Clearance 2 and 3	0.0254-0.0508 mm	0.0010-0.0020 in
Main Bearing To Journal Clearance 4	0.0229-0.0457 mm	0.0009-0.0018 in
Rod Bearing Clearance	0.0127-0.0660 mm	0.0005-0.0026 in
Crankshaft End Play	0.076-0.276 mm	0.003-0.011 in
Connecting Rod
Rod Side Clearance	0.102-0.508 mm	0.004-0.0200 in
Connecting Rod Large End Bore ID	60.295-60.312 mm	2.37378-2.3745 in
Camshaft
Journal Diameter	47.655-46.858 mm	1.8462-1.8448 in
Bearing Inside Diameter 1 and 4	46.970-46.934 mm	1.8428-1.8492 in
Bearing Inside Diameter 2 and 3	46.977-46.942 mm	1.8481-1.8495 in
Bearing-to-Journal Clearance	0.041-0.119 mm	0.0016-0.0047 in
Intake Maximum Lobe Lift	6.55 mm	0.258 in
Exhaust Maximum Lobe Lift	6.48 mm	0.255 in
Balance Shaft
End Play	0.0-0.171 mm	0.0-0.0067 in
Rear Journal Diameter	38.085-38.105 mm	1.4994-1.5002 in
Radial Play-Front, Bearing Clearance	0.0-0.026 mm	0.0-0.0010 in
Rear Bearing To Journal Clearance	0.0127-0.109 mm	0.0005-0.0043 in
Drive Gear Lash	0.050-0.125 mm	0.002-0.0049 in
Bearing Bore Diameter-Front	51.973-51.999 mm	2.0462-2.0472 in
Bearing Bore Diameter-Rear, In Block	47.584-47.612 mm	1.8735-1.8745 in
Bearing Inside Diameter-Rear	38.118-38.194 mm	1.5007-1.5037 in
Valve System
Lifter	Hydraulic
Rocker Arm Ratio	1.6:1
Face Angle	45°
Seat Angle	45°
Minimum Margin	0.635 mm	0.025 in
Seat Runout-Maximum	0.050 mm	0.002 in
Seat Width-Intake	1.53-2.03 mm	0.060-0.080 in
Seat Width-Exhaust	2.29-2.79 mm	0.090-0.110 in
Stem Height-All	49.15-50.17 mm	1.935-1.975 in
Stem Clearance-All	0.038-0.089 mm	0.0015-0.0032 in
Valve Spring
Free Length	49.78 mm	1.960 in
Load-Closed	334 N @ 43.69 mm	75 lb @ 1.72 in
Load-Open	1014 N @ 32.4 mm	228 lb @ 1.277 in
Installed Height	42.93-44.45 mm	1.690-1.720 in
Approximate Number of Active Coils	4.48
Approximate Number of Total Coils	6.60
Flywheel
Runout-Maximum	0.38 mm	0.015 in