"Buick Trademark(s) used with the written permission of General Motors"
 
 
Home Forums Garage Classifieds Reference

Buick 225 Engine Specifications and Blueprinting

225 V-6

General Specifications for the 198 and 225 Cubic Inch V-6. The following information has been directly complied from original Buick service manuals.


BOLT TORQUE SPECIFICATIONS

Area Lb. Ft.
Crankshaft Bearing Caps to Cylinder Block 95-120
Connecting Rods 30-40
Cylinder Head to Cylinder Block 65-80
Fan Driving Pulley to Harmonic Balancer 18-25
Flywheel to Crankshaft (Auto. & Manual) 50-65
Oil Pan to Cylinder Block 9-13
Oil Pan Drain Plug 25-35
Oil Pump Cover to Timing Chain Cover 8-12
Oil Pump Pressure Regulator Retainer 25-30
Oil Screen Housing to Cylinder Block 6-9
Oil Pan Baffle to Cylinder Block 9-13
Oil Gallery Plugs 20-30
Filter Assembly to Pump Cover 10-15
Timing Chain Cover to Block 17-23
Water Pump Cover to Timing Chain Cover 6-8
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
Air Cleaner Stud 17-23 Lb. In.
Air Cleaner Wing Nut 17-23 Lb. In.
Fuel Pump to Cylinder Block 17-23
Motor Mount to Cylinder Block 50-75
Fuel Pump Eccentric and Timing Chain Sprocket to Camshaft 40-55
Rocker Arm Cover to Cylinder Head 3 to 5
Rocker Arm Shaft Bracket to Cylinder Head 25-35
Delcotron Bracket to Cylinder Head 30 to 40
Delcotron Bracket to Water Pump Timing Chain Cover 18-25
Delcotron Mounting Bracket thru Delcotron to Cylinder Head at Pivot Location 30-40
Starting Motor to Block 30-40
Starting Motor Brace to Block 9-13
Starting Motor Brace to Starting Motor 9-13
Distributor Hold down Clamp 10-15
Spark Plugs 25-35
Manual Lower Flywheel Housing 9-13
Flywheel Housing to Cylinder Block 30-40
Timing Chain Damper to Cylinder Block Bolt 6-9
Bolt - Special Moveable Timing Chain Damper 10-15
Buick 225 Head Torque Patter Buick 225 head bolt torque pattern.



GENERAL SPECIFICATIONS
Engine Type 90° V-6
Valve Arrangement In Head
Bore and Stroke 3.750 x 3.400
Piston Displacement 225 Cu. In.
Compression Ratio 9.0 to 1
Brake Horsepower @ RPM 160 BHP @ 4400
Torque § RPM 225 Lb. Ft. @ 2400
Octane Requirement 85 Motor Method
Octane Requirement 93 Research Method
Taxable Horsepower 33.748
Cylinder Numbers Front to Rear Right Bank 2-4-6
Left Bank 1-3-5
Firing Order 1-6-5-4-3-2
Cylinder Block Material Cast Iron
Cylinder Head Material Cast Iron
Engine Idle Speed
.....Manual 550
.....Automatic 550 Drive
.....AC Auto 600 Drive

Piston and Piston Pin Specifications
Piston Material Cast Aluminum Alloy
Piston Treatment Tin Plated
Piston Pin Material SAE 1018
Piston Pin Type Pressed In Rod
Connecting Rod Specifications
Material Pearlitic Malleable Iron
Bearing Type Removable Steel Backed
Bearing Material M100 Durex
Rod Length 5.960
Rod Width .835

Ring Specifications, Compression Ring Material & Surface Treatment
#1 Iron - Chrome Plated
#2 Iron - Lubricated
Oil Ring Type Dual Steel Rail with Spacer
Oil Ring Expander Steel Humped Ring
Location of Rings Above Piston Pin

Crankshaft Specifications
Material Pearlitic Malleable Iron
Bearings 4 Replaceable Liner
Bearing Material M100 Durex
Bearing Taking End Thrust #2

Camshaft Specifications
Material Cast Alloy Iron
Bearings Steel Backed Babbitt
Number of Bearings 4
Camshaft Location Above Crankshaft at Center of "V"
Type of Drive Chain
No. of Links 54
Crankshaft Sprocket Sintered Iron
Camshaft Sprocket Nylon Coated Aluminum

Valve Specifications
Intake Valve Material SAE 1041 Steel
Exhaust Valve Material GM-N82152(21-4N)
Valve Lifter Type Hydraulic
Valve Spring Single Helical

Lubrication System Specifications
Type of Lubrication Main Bearings Pressure
Connecting Rods Pressure
Piston Pins Splash
Camshaft Bearings Pressure
Timing Chain Splash & Nozzle
Cylinder Walls Splash & Nozzle
Oil Pump Type Gear Driven
Normal Oil Pressure 33 Ibs. @ 2400 RPM
Oil Pressure Sending Unit Electrical
Oil Intake Screened Tube
Oil Filter System Full Flow
Filter Type Throw-Away Element & Can
Crankcase Capacity Less Filter 4 qts.
With Filter 5 qts.

Cooling System Specifications
System Type Pressurized Utilizing Cross-Flow Radiator
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 Capacity With Heater 11.2 qts.
W/O Heater 10.5 qts.
With AC 11.2 qts.

Fan Diameter and Number of Blades
Less AC 17" - 4
With AC 18" - 7
Fan Drive Less AC Water Pump Shaft
With AC Torque and Temperature Sensitive Clutch

ENGINE DIMENSIONS AND FITS
Deck Height 10.187
Rings, Piston, and Piston Pin Specifications
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 .1880" - .1955"
....#3 - Oil Ring .1880" - .1955"
Ring Width
....#1 - Compression Ring .0785" - .0790"
....#2 - Compression Ring .0770" - .0780"
....#3 - Oil Ring .1810" - .187"
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 & Amount Offset in Piston .040" Toward High Thrust Side
*A11 Measurements in Inches Unless Otherwise Specified.

Connecting Rod Specifications
Bearing Length .737"
Bearing Clearance (Limits) .0020" - .0023"
End Play - Total for both Rods .006" - .014"

Crankshaft Specifications
End Play at Thrust Bearing .004" - .008"
Main Bearing Journal Diameter 2.4995"
Crank pin Journal Diameter 2.0000"
Main Bearing Overall Length
....#1 .864"
....#2 .1057"
....#3 .864"
....#4 .864"
Main Bearing to Journal Clearance .0005" - .0021"

Camshaft Specifications
Bearing Journal Diameter
....#1 1.755" - 1.756"
....#2 1.725" - 1.726"
....#3 1.695" - 1.696"
....#4 1.665" - 1.666"
Journal Clearance in Bearings

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 1.625"
Seat Angle 45°
Stem Diameter .3412" Top - .3407" Bottom
Clearance in Guide Top .001"-.003" - Bottom .0015"-.0035"
Stem Height 1.8450-1.8750"
Exhaust Valve
Head Diameter 1.3750"
Seat Angle 45°
Stem Diameter 3407" Top - .3402" Bottom
Clearance in Guide Top .0015"-.0035" - Bottom .002"-.004"
Installed Stem Height 1.8450-1.8750"
Valve Spring
Valve Closed - Pounds @ Length 64 ± 5 @ 1.727"
Valve Open - Pounds @ Length 164 ± 6 @ 1.340"

Cubic Inches V-225 V-198 V-231
Bore 3.750 3.625 3.800
Stroke 3.400 3.200 3.400
Rod Length 5.960 - 5.960
Rod / Stroke Ratio 1.7529 - -
Bore / Stroke Ratio 1.1029 - -
Bore Spacing 4.240 - -
Deck Height 10.187 10.187 9.535
Comp. Distance 1.870 1.844-1.860 -
       
       
Submitted by Bob K. Mando