Buick 300-340 Engine Specifications and Blueprinting

General Specifications for the 1966 Buick 300 and 340 Cubic Inch Engines.

The following information has been directly complied from original Buick service manuals for the respective year of vehicle manufacture. These specifications should also be correct for the 1966 model year.

        contributed by Aaron

Bolt Torque Specifications
AREA:	Torque Lb. Ft.
Spark Plugs	25-35
Crankshaft bearing caps to cylinder block	95-120
Connecting rods	30-40
Cylinder head to cylinder block	65-80
Harmonic balancer to crankshaft	140 MINIMUM
Fan driving pulley to harmonic balancer	18-25
Flywheel to crankshaft (both auto and manual)	50-65
Oil pan to cylinder block	09-13
Oil pan drain plug	25-35
Oil pump cover to timing chain cover	08-12
Oil pump pressure regulator retainer	25-30
Oil screen housing to cylinder block	06-09
Oil pan baffle to cylinder block	09-13
Oil galley plugs	20-30
Filter assembly to pump cover	10-15
Timing chain cover to block	17-23
Water pump cover to timing chain cover	06-08
Fan driven pulley	17-23
Thermostat housing to intake manifold	17-23
Intake manifold to cylinder head	45-55
Exhaust manifold to cylinder head	10-15
Carburetor to intake manifold	10-15
Fuel pump to cylinder block	17-23
Motor mount to cylinder block	50-75
Fuel pump eccentric to timing chain sprocket to camshaft	40-55
Rocker arm cover to cylinder head	03-05
Rocker arm shaft bracket to cylinder head	25-35
Delcotron (alternator) bracket to cylinder head	30-40
Delcotron (alternator) bracket to water pump timing chain cover	18-25
Delcotron (alternator) mounting bracket thru Delcotron to cylinder head at pivot location	30-40
Starting motor to block	30-40
Starting motor brace to block	09-13
Starter motor brace to starting motor	09-13
Distributor hold down clamp	10-15
Manual lower flywheel housing plate (inspection cover)	09-13
Flywheel housing to cylinder block	30-40
Fuel filter to cylinder head	10-15

Head bolt torque pattern for Buick 300-340 engines.

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GENERAL SPECIFICATIONS

	Wildcat 310 (300 Cu, In.)	Wildcat 350 (340 Cu In.)	Wildcat 375 (340 Cu. In)
Code number prefix	ML	MA	MB
Export code number prefix	MM	MC	N/A
Engine type	90° V8	90° V8	90° V8
Bore and stroke	3.750 x 3.400	3.750 x 3.850	3.750 x 3.850
Piston Displacement	300 Cu. In.	340 Cu In.	340 Cu. In.
Carburetor type	2 barrel	2 barrel	4 barrel
Compression ratio	9.0:1	9.0:1	10.25:1
Gasoline requirements	regular	regular	premium
Brake horsepower @ RPM	210/4600	220/4000	260/4000
Maximum torque @ RPM	310/2400	340/2400	365/2800
Taxable horsepower	33.748	45.0	45.0
Octane requirements motor	85	85	90
Octane requirements research	93	93	99
Cylinder numbers front to rear
Left bank	1-3-5-7	1-3-5-7	1-3-5-7
Right bank	2-4-6-8	2-4-6-8	2-4-6-8
Firing Order	1-8-4-3-6-5-7-2	1-8-4-3-6-5-7-2	1-8-4-3-6-5-7-2

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Piston and pin specifications: Piston Material Cast aluminum alloy Type Divorced skirt Finish Cam ground Piston Pins Material Extruded SAE-1018 Type Pressed in rod Crankshaft specifications: Material Pearlitic malleable iron Bearings 5 replaceable steel backed Bearing material #1, #2, #3, and #4 M/400 #5 M/100 Durex Bearing taking thrust load #3 Camshaft specifications: Material Cast alloy iron Bearings Steel backed Babbitt Number of bearings 5 Drive Chain Number of links 54 Crankshaft sprocket Sintered Iron Camshaft sprocket Nylon coated aluminum Lubrication system specifications: Type of lubrication Main bearings Pressure Connecting rods Pressure Piston pins Splash Camshaft bearings Pressure Timing chain Splash and nozzle Cylinder walls Splash and nozzle Oil pump type Gear driven Normal oil pressure 33lbs. @ 2400 RPM Oil pressure sending unit Electrical Oil intake Stationary Oil filter system Full flow Filter type Throw away element and can Crankcase capacity Less filter 4qts. With filter 5qts. ENGINE DIMENTIONS AND FITS General: Piston Clearance limits Top land .0265-.0345 Skirt- Top .0005-.0011 Skirt- Bottom .0005-.0021 Ring groove depth #1 compression ring .1855-.1930 #2 compression ring .188-.1955 #3 Oil ring .188-.1955 Ring width #1 compression ring .0785-.0789 #2 compression ring .0770-.0780 #3 Oil ring .1810-.1870 Ring gap #1 compression ring .010-.020 #2 compression ring .010-.020 #3 Oil ring .015-.035 Piston pin length 3.060 Diameter of pin .9394-.9397 Clearance In piston .0001-.0004 In rod .0007-.0015 Press Direction and amount off set in piston .040 Toward high thrust side *All measurements are in inches unless otherwise specified Camshaft specifications: Bearing journal diameter #1 1.785-1.786 #2 1.755-1.756 #3 1.725-1.726 #4 1.695-1.696 #5 1.665-1.666 Journal clearance in bearings .005-.0035 (#2, #3, #4, & #5) Connecting rod specifications: Bearing length .737 Bearing clearance (Limits) .0020-.0023 End play- Total for both rods .006-.014

Connecting rods: Material Pearlitic malleable iron Rod bearing Removable steel backed M/400 Ring specifications: #1 compression Cast iron-chrome plated #2 compression Cast iron-lubricated Oil control Steel-uncoated Oil ring expander Steel humped ring Ring locations Above pin Valve specifications: Intake valve material SAE 1041 steel Exhaust valve material GM-N82152 (21-4N) Valve lifter mechanism Hydraulic Valve spring Single helical Cooling system specifications: System type Pressure Radiator cap relief pressure 15 PSI Thermostat Choke type opening at 180° Water pump Type Centrifugal GPM @ RPM 14 @ 1000 Drive V-Belt Bearings Double row By-pass recirculation type External Cooling system capacities:   (300 Cu. In.) (340 Cu. In.) With heater 12.7qts. 12.7qts. W/O heater 12.2qts. 12.2qts. With air conditioning (all except 300 station wagon) 14.0qts. 14.7qts. With air conditioning (Station Wagon) 14.7qts. 14.7qts. Fan diameter and number of blades: Less AC 18" x 4 With AC 18" x 7 Fan Drive Less AC Water pump shaft With AC Torque and temperature sensitive clutch Valve system specifications: Rocker arm ratio 1.6 to 1 Rocker arm clearance on shaft .0017-.0032 Valve lifter diameter .8422-.8427 Valve lifter clearance in crankcase .0015-.003 Valve lifter leak down rate 12 to 60 sec. In test fixture Intake valve Head diameter 1.8175-1.8075 Seat angle 45° Stem diameter (top) .3415-.3412 (bottom) .3405 Clearance in guide .0012-.0032 & .0003 max taper Valve Stem Height 1.880-1.9100 Valve spring Valve closed- Pounds @ length 64 ± 5 @ 1.727 Valve open- Pounds @ length 164 ± 6 @ 1.340 Exhaust Valve Head diameter 1.380-1.370 Seat angle 45° Stem diameter (top) .3402-.3412 (bottom) .3397-.3407 Clearance in guide (top) .0015-.0035 (bottom) .0021-.004 Valve Stem Height 1.880-1.9100 Valve spring Valve closed- Pound @ length 64 ± 5 @ 1.727 Valve open- Pound @ length 164 ± 6 @ 1.340 Valve stem, installed height 1.880"-1.910 (1.925" reported) Crankshaft specifications: End play at thrust bearing .004-.008 Main bearing journal diameter, 300 2.4995 Main bearing journal diameter3 340 2.9995 Crank pin journal diameter 2.0000 Main bearing overall length #1 .864 #2 .864 #3 1.057 #4 .864 #5 .864 Main bearing to journal clearance .0004-.0015