Engine Specifications
ENGINE SUMMARY
| Make | Pontiac |
| Displacement - Advertised | 400 |
| Layout | V |
| Cylinders | 8 |
| Year | 1970 |
| Model | Ram Air IV |
| Description | Eng code WH, Man trans |
| Stock/Modified | Stock OE |
| Builder | Pontiac |
| HP Advertised | 370 |
| RPM@HP Advertised | 5500 |
| Bore | 4.12 |
| Stroke | 3.75 |
| Rod Length | 6.625 |
| Bore/Stroke Ratio | 1.099 |
| Rod/Stroke Ratio | 1.767 |
| Compression Ratio | 10.5 |
| Bore Angle | 90 |
| Firing Order | 1-8-4-3-6-5-7-2 |
| Rotation (from front) | CW |
| Notes | Test RA IV engine |
SHORT BLOCK
| Block: | |
| Manufacturer | Pontiac |
| Part Number | 9799915 |
| Description | 1970 400 Ram Air IV |
| Deck Height | 10.24000 |
| Bore Spacing | 4.62000 |
| Material | Iron |
| Main Caps | 4 bolt |
| Weight | 202.000 |
| Notes | Test RA IV block |
CRANKSHAFT:
| Crankshaft: | |
| Manufacturer | Pontiac |
| Part Number | 9794054 |
| Description | Test RA IV crank |
| Stroke | 3.750000 |
| Main Journal Dia | 3.000000 |
| Rod Journal Dia | 2.250000 |
| Design | 90 deg |
| Material | Nodular Iron |
| Weight | 70.000 |
| Notes | WH, WW, XN, XP engines, 0.001 more clearance. |
CONNECTING RODS
| Connecting Rods: | |
| Manufacturer | Pontiac |
| Part Number | 541000 |
| Description | generic cast V8 |
| Length | 6.62500 |
| Big End Bore Dia | 2.37400 |
| Pin Bore Dia | 0.98000 |
| Big End Width | 0.99600 |
| Pin End Width | 1.05000 |
| Crank Pin Dia | 2.25000 |
| Wrist Pin Dia | 0.98000 |
| Design | I-Beam |
| Construction | Cast |
| Material | Iron |
| Fasteners | 3/8" |
| Weight, Total | 900.000 |
| Weight, Big End | 450.000 |
| Weight, Small End | 350.000 |
| Weight, Bearings End | 33.000 |
| Notes | test rod |
Pistons:
| Pistons: | |
| Manufacturer | Pontiac |
| Part Number | 646416416 |
| Description | 400 Ram Air 4 '70 |
| Compression Height | 1.72000 |
| Dome Volume | -8.000 |
| Crevice Volume Included | yes |
| Top Land Dia | 4.05000 |
| Top Land Depth | 0.22300 |
| Construction | Forged |
| Material | aluminum |
| Skirt Style | full |
| Skirt Coating | none |
| Top Coating | none |
| Pin Dia | 0.980000 |
| Pin Bore Dia | 0.980200 |
| Pin Length | 3.06000 |
| Pin Retention | Pressed |
| Weight | 562.000 |
| Ring Tension | 25.000 |
| Ring Leakage | 3.000 |
| Ring Package Weight | 29.000 |
| Pin Weight (incl retainer) | 125.000 |
| Notes | test ra iv piston |
Oil System:
| Oil System: | |
| Type | Stock Wet Sump |
CYLINDER HEADS
| Cylinder Head - Design: | |
| Manufacturer | Pontiac |
| Part Number | 65464135 |
| Description | '70 Ram Air IV |
| Porting Level | None |
| Chamber Design | Closed |
| Chamber Volume | 73.000 |
| Material | Iron |
| # Intake Valves per cyl | 1 |
| # Intake Ports per cyl | 1 |
| Intake Valve Dia | 2.11000 |
| Intake Port Volume | 185.000 |
| # Exhaust Valves per cyl | 1 |
| # Exhaust Ports per cyl | 1 |
| Exhaust Valve Dia | 1.77000 |
| Exhaust Port Volume | 155.000 |
| Notes | test RA IV head |
CYLINDER HEAD - AIRFLOW
| Cylinder Head - Airflow: | ||
| Test Pressure | xxx | |
| Lift | Intake | Exhaust |
| 0.100 | xxx | xxx |
| 0.200 | xxx | xxx |
| 0.300 | xxx | xxx |
| 0.400 | xxx | xxx |
| 0.500 | xxx | xxx |
| 0.600 | xxx | xxx |
| 0.700 | xxx | xxx |
| 0.800 | xxx | xxx |
| 0.900 | xxx | xxx |
| 1.000 | xxx | xxx |
HEAD GASKET:
| Head Gasket: | |
| Gasket Thickness | 0.0410 |
| Gasket Bore Dia | Pontiac |
| Notes | test head gasket |
CAMSHAFT & VALVETRAIN
| Camshaft: | |
| Manufacturer | Pontiac |
| Part Number | 9794041 |
| Description | '70 Ram Air IV |
| Lifter Type | Hydraulic |
| Rating Method | Advertised |
| Intake Duration - Advertised | 282.000 |
| Intake Duration @ .050 | 262.000 |
| Intake Lift | 0.51200 |
| Exhaust Duration - Advertised | 320.00000 |
| Exhaust Duration @ .050 | 262.00000 |
| Exhaust Lift | 0.51200 |
| Lobe Separation | 112.000 |
| Install Offset | 0.000 |
| Notes | test camshaft |
ROCKER ARMS:
| Rocker Arms: | |
| Manufacturer | Pontiac |
| Part Number Dia | 64654654 |
| Description | Ram Air IV |
| Design | Stamped |
| Ratio - Intake | 1.6500 |
| Ratio - Exhaust | 1.6500 |
| Notes | test rocker |
PUSHRODS
| Pushrods: | |
| Manufacturer | Pontiac |
| Part Number | 64654654 |
| Description | Ram Air IV |
| Diameter | 0.34375 |
| Length | 10.05000 |
| Notes | test pushrod |
INDUCTION & FUEL DELIVERY:
THROTTLE BODY / CARBURETOR:
| Throttle Body / Carburetor: | |
| Manufacturer | Pontiac |
| Part Number Dia | 46465465 |
| Description | Qjet |
| Airflow Rating | 680.000 |
| Notes | test carb |
INTAKE MANIFOLD
| Intake Manifold: | |
| Manufacturer | Pontiac |
| Part Number Dia | 797444 |
| Description | Alum RA IV |
| Design | Dual Plane |
| Notes | test manifold |
EXHAUST SYSTEM:
EXHAUST MANIFOLD(S)
| Exhaust Manifold: | |
| Manufacturer | Pontiac |
| Part Number Dia | fgh654654 |
| Description | cast iron |
| Primary Tube Diameter | 1.6500 |
| Primary Tube Length | 28.0000 |
| Collector Diameter | 2.8000 |
| Collector Length | 3.0000 |
| Notes | test exhaust manifold |
MUFFLER(S):
| Mufflers: | |
| Manufacturer | Pontiac |
| Part Number | asdfsaf444 |
| Description | bahblahblah |
| Type | OE quiet |
| Notes | test muffler |