Buick 400-430-455 Engine Specifications and Blueprinting
General Specifications for the 1968 400/430 and 1970 Buick 455 Cubic Inch Engines. The following information has been directly complied from original Buick service manuals for the respective year of vehicle manufacture.
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| BOLT TORQUE SPECIFICATIONS
Use a reliable torque wrench to obtain the figures listed below. This will prevent straining or distorting the parts as well as preventing thread damage. These specifications are for clean and lightly lubricated threads only. Dry or dirty threads produce friction which prevents accurate measurement of the actual torque. It is important that these specifications be strictly observed. Over tightening can damage threads. This will prevent attainment of the proper torque and will require replacement of the damaged part.
| Area |
Lb. Ft. |
| Spark Plugs |
15 |
| Crankshaft Bearing Caps to Cylinder Block |
110 |
| Connecting Rods |
45 |
| Cylinder Head to Cylinder Block |
100 |
| Harmonic Balancer to Crankshaft |
200 Minimum |
| Fan Driving Pulley to Harmonic Balancer |
23 |
| Flywheel to Crankshaft (Auto. & Manual) |
60 |
| Oil Pan Baffle to Cylinder Block |
455-13, 400/430-8 |
| Oil Pan to Cylinder Block |
14 |
| Oil Pan Drain Plug |
30 |
| Oil Pump Cover to Timing Chain Cover |
10 |
| Oil Pump Pressure Regulator Retainer |
455-35, 400/430-25 |
| Oil Pick-Up Tube & Screen Housing Assembly to Oil Pump |
8 |
| Oil Gallery Plugs |
25 |
| Oil Pressure Switch to Cylinder Block |
455-23, 400/430-25 |
| Oil Filter to Cylinder Block |
455-13, 400/430-12 |
| Timing Chain Cover to Block |
455-29, 400/430-30 |
| Water Pump Cover to Timing Chain Cover |
455-7, 400/430-8 |
| Fan Driven Pulley |
20 |
| Thermostat Housing to Intake Manifold |
20 |
| Automatic Choke Cover to Intake Manifold |
8 |
| Intake Manifold to Cylinder Head |
455-55, 400/430-50 |
| Exhaust Manifold to Cylinder Head |
18 |
| Carburetor to Intake Manifold |
455-13, 400/430-12 |
| Fuel Pump to Cylinder Block |
20 |
| Motor Mount to Cylinder Block |
455-63, 400/430-70 |
| Fuel Pump Eccentric and Timing Chain Sprocket to Camshaft |
22 |
| Rocker Arm Cover to Cylinder Head |
4 |
| Rocker Arm Shaft to Cylinder Head |
455-25, 400/430-30 |
| Delcotron Bracket to Cylinder Head |
35 |
| Delcotron Adjusting Mounting Bracket to Cylinder Head |
455-35, 400/430-22 |
| Delcotron Mounting Bracket Thru Delcotron to Cylinder Head at Pivot Location |
35 |
| Starting Motor to Block |
35 |
| Starting Motor Brace to Block |
11 |
| Starting Motor Brace to Starter |
11 |
| Distributor Hold-Down Clamp |
455-13, 400/430-12 |
| Flywheel Housing to Cylinder Block |
35 |
| Automatic Lower Flywheel Housing Plate |
4 |
Buick 400-430-455 Head bolt torque pattern. |
GENERAL SPECIFICATIONS
| General |
| |
400-4 |
430-4 |
455-4 |
455-4, Stage I |
455-4 |
| Code Number Prefix |
PR |
PD |
SR |
SS |
SF |
| Export Code Number Prefix |
N/A |
PE |
N/A |
N/A |
N/A |
| Engine Type |
90° V-8 |
| Bore and Stroke |
4.040 x 3.900 |
4.1875 x 3.900 |
4.3125 x 3.900 |
4.3125 x 3.900 |
4.3125 x 3.900 |
| Piston Displacement |
400 cu. in. |
430 cu. in. |
455 cu. in. |
455 cu. in. |
455 cu. in. |
| Carburetor Type |
4 BBL. |
| Compression Ratio |
10.25:1 |
10.25:1 |
10.0:1 |
10.50:1 |
10.0:1 |
| Gasoline Requirements |
Premium |
| Brake Horsepower @ RPM |
340@5000 |
360@5000 |
350@4600 |
360@4600 |
370@4600 |
| Maximum Torque @ RPM |
440@3200 |
475@3200 |
510@2600 |
510@2600 |
510@2800 |
| Taxable Horsepower |
51.91 |
56.1 |
59.5 |
59.5 |
59.5 |
| Octane Requirements - Motor |
90 |
| Octane Requirements - Research |
99 |
| Cylinder Numbers - Front to Rear - Left Bank |
1-3-5-7 |
| Cylinder Numbers - Front to Rear - center Bank |
2-4-6-8 |
| Firing Order |
1-8-4-3-6-5-7-2 |
| 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 |
| Connecting Rods |
| Material |
400/430 Forged - SAE-1141 Steel, 455 SAE-1053 |
| Rod Bearing |
Removable Steel Backed M/400 |
| Ring Specifications |
| #1 Compression |
Cast Iron Molybdenum Coated |
| #2 Compression |
Cast Iron-Lubricated |
| Oil Control |
SAE-1070 Steel-Chrome Plated |
| Oil Ring Expander |
Abutment Type |
| Ring Locations |
Above Pin |
| Crankshaft Specifications |
| Material |
Nodular Iron |
| Bearing Material |
Steel Backed M/400 Aluminum - #5 Durex M/100A |
| Bearing Taking End Thrust |
#3 |
| Camshaft Specifications |
| Material |
Cast Alloy Iron |
| Bearings |
Steel Backed Babbitt |
| Number of Bearings |
5 |
| Drive |
Chain |
| Number of Links |
48 |
| Crankshaft Sprocket |
Sintered Iron |
| Camshaft Sprocket |
Nylon Coated Aluminum |
| Valve Specifications |
| Intake Valve Material |
Aluminized Face and Chrome Flash Stem SAE 1041 Steel |
| Exhaust Valve Material |
Aluminized Face and Chrome Flash Stem GN-N82152 (21-4N) |
| Valve Lifter Mechanism |
Hydraulic |
| Valve Spring |
Single Helical |
|
| Lubrication System Specifications |
| Type of Lubrication |
|
| Main Bearings |
Pressure |
| Connecting Rods |
Pressure |
| Piston Pins |
Splash |
| Camshaft Bearing |
Pressure |
| Timing Chain |
Drip from Front Cam Bearing |
| Cylinder Walls |
Splash & Nozzle |
| Oil Pump Type |
Gear Driven |
| Normal Oil Pressure |
40 Ibs. @ 2400 RPM |
| Oil Pressure Sending Unit |
Electrical |
| Oil Intake |
Stationary |
| Oil Filter System |
Full Flow |
| Filler Type |
Throw-Away Element & Can |
| Crankcase Capacity |
|
| Less Filter |
4 qts. |
| With Filter |
5 qts. |
| Cooling System Specifications |
| System Type |
Pressure |
| Radiator Cap Relief Pressure |
15 psi |
| Thermostat |
Choke Type Opening at 190° |
| Water Pump Type |
Centrifugal |
| GPM @ RPM |
15 @ 1000 |
| Drive |
V-Belt |
| Bearings |
Double Row |
| By-Pass Recirculation Type |
Internal |
| Cooling System Capacities |
|
| With Heater |
400-16.2 qts., 430-16.7 qts., 455-19.7 qts. |
| With Air Conditioning |
400-16.7 qts, 430-17.0 qts., 455-20.0 qts. |
| Fan Diameter and Number of Blades |
18"X4 |
GS400 Less AC, GS455
Wildcat Less AC
Electra Less AC |
18"X7 |
GS400 With AC
GS455 With AC
Riviera Less AC |
20"X5 |
Wildcat With AC
Electra With AC
Riviera With AC |
|
| Fan Drive |
|
| Less AC |
Water Pump Shaft |
| With AC |
400/430 Thermostatic Controlled Clutch
455 Torque and Temperature Sensitive Clutch |
| Engine Dimensions and Fits |
| Piston Clearance Limits* |
| |
400 Cu. In. |
430 Cu. In. |
455 Cu. In. |
| Top Land |
.034-.042 |
.0343-.0423 |
.0343-.0423 |
| Skirt - Top |
.0007-.0013 |
.0007-.0013 |
.0007-.0013 |
| Skirt - Bottom |
.0017-.0033 |
.0017-.0033 |
.0017-.0033 |
| Ring Groove |
| #1 - Compression Ring |
.2090-.2165 |
.2090-.2165 |
.2090-.2165 |
| #2 - Compression Ring |
.2115-.2190 |
.2115-.2190 |
.2115-.2190 |
| #3 - Oil Ring |
.1815-.1890 |
.1815-.1890 |
.1815-.1890 |
| Ring Width |
| #1 - Compression Ring |
.077-.078 |
.077-.078 |
.077-.078 |
| #2 - Compression Ring |
.077-.078 |
.077-.078 |
.077-.078 |
| #3 - Oil Ring |
.023-.025 |
.023-.025 |
.023-.025 |
| Ring Gap |
| #1 - Compression Ring |
.013-.023 |
.013-.023 |
.013-.023 |
| #2 - Compression Ring |
.013-.023 |
.013-.023 |
.013-.023 |
| #3 - Oil Ring |
.015-.055 |
.015-.055 |
.015-.055 |
| Piston Pin Length |
3.520 |
3.520 |
3.520 |
| Diameter of Pin |
.9994-.9997 |
.9994-.9997 |
.9994-.9997 |
| Clearance |
| In Piston |
.0001-.0004 |
.0001-.0004 |
.0001-.0004 |
| In Rod |
.00075-.00125
press |
.00075-.00125
press |
.00075-.00125
press |
| Direction & Amount Offset in Piston |
.060 Offset
Major Thrust |
.060 Offset
Major Thrust |
.060 Offset
Major Thrust |
| *A11 Measurements in Inches Unless Otherwise Specified. |
| Connecting Rod Specifications |
| |
400 Cu. In. |
430 Cu. In. |
455 Cu. In. |
| Bearing Length |
.821 |
.821 |
.821 |
| Bearing Clearance (Limits) |
.0002-.0023 |
.0002-.0023 |
.0002-.0023 |
| End Play-Total for Both Rods |
.005-.012 |
.005-.012 |
.005-.012 |
| Crankshaft Specifications 400/430/455 |
| End Play at Thrust Bearing |
.003-.009 |
| Main Bearing Journal Diameter |
3.25 |
| Crank pin Journal Diameter |
2.249-2.250 |
| Main Bearing Overall Length |
| #1 |
.865 |
| #2 |
.865 |
| #3 |
1.057 |
| #4 |
.865 |
| #5 |
1.143 |
| Main Bearing to Journal Clearance |
.0007-.0018 |
| Bearing Journal Diameter |
| #1
| 1.785-1.786 |
| #2
| 1.785-1.786 |
| #3
| 1.785-1.786 |
| #4
| 1.785-1.786 |
| #5
| 1.785-1.786 |
| Valve System Specifications |
| Rocker Arm Ratio
| 1967-68 400/430 - 1.59 to 1, aluminum
1969-70, 400/455 - 1.54 to 1, stamped steel
1971+, 455 - 1.6 to 1, stamped steel |
| Rocker Arm Clearance on Shaft
| .0015-.0030 |
| Valve Lifter Diameter
| .8427-.8422 |
| Valve Lifter Clearance in Crankcase
| .0008-.0023 |
| Valve Lifter Leak down Rate
| 12 to 60 Sec. in Test Fixture |
| Intake Valve |
| Head Diameter
| 2.000 |
| Seat Angle
| 45° |
| Stem Diameter
| .3725 ± .0005-Max. Allowable Taper to be .0003 with Smallest Dia. @ Valve Head End |
| Clearance in Guide
| .0015-.0035 & .0003 Max. Taper |
| Valve Stem Height |
2.0320"-2.0620", some 2.0900" - 2.1200 |
| Valve Spring |
| Valve Closed - Pounds @ Length
| 72 ± 5@1.890 |
| Valve Open - Pounds @ Length
| 177 ± 7@1.450 |
| Exhaust Valve |
| Head Diameter
| 1.625 |
| Seat Angle
| 45° |
| Stem Diameter
| 400/430, .3723 Min, and .3730 Max |
| Clearance in Guide
| .0015-.0032 & .0002 Max. Taper |
| Valve Stem Height |
2.0320"-2.0620", some 2.0900" - 2.1200 |
| Valve Spring (Inner) |
| Valve Closed - Pounds @ Length
| 72 ± 5@1.890 |
| Valve Open - Pounds @ Length
| 177 ± 7@1.450 |
Additional Blueprint Specifications for the Buick 400/430/455
| Cubic Inches |
Bore |
Stroke |
Rod Length |
Rod Width |
Rod/Stroke Ratio |
Bore/Stroke Ratio |
Bore Spacing |
Deck Height |
| 400 |
4.040 |
3.900 |
6.607 |
0.928 |
1.6923 |
1.0359 |
4.750 |
10.57 |
| 430 |
4.1875 |
3.900 |
6.607 |
0.928 |
1.6923 |
1.0737 |
4.750 |
10.57 |
| 455 |
4.3125 |
3.900 |
6.607 |
0.928 |
1.6923 |
1.1058 |
4.750 |
10.57 |
|
Buick 400/430/455 rear Main Seal, use Fel-Pro BS 30135 (Ford 200 L6) seal, or Fel-Pro BS40012 (Caddilac 472 May nead trim).
