The Pontiac Engine

  • Pontiac Firing Order


    Pontiac V8

    265, 301, 307*, 326, 350, 389, 400, 421, 428, 455


    Firing Order


    Cylinder Numbering Distributor Rotation

    Rotor Under Cap Spins:

    Counter

    Clockwise

    (*307 rotates Clockwise)

    These graphics courtesy of Boxwrench.com
  • Pontiac Head Specs

    Click Here for the Edelbrock Aluminum Head Installation Sheet


    PONTIAC HEAD CHART
    CASTING
    NUMBER     		YEAR & FACTORY APPLICATION CHAMBER
    VOL# CC'S    		 EXHAUST
    PORT     		NOTEWORTHY
    ATTRIBUTES
    528511 1958 370 62 D-Port 1.88/1.6 55-60 INT MAN
    538177 61-62 389 62 D-Port 1.88/1.6 61-64 INT MAN
    543797 63 389 62 D-Port 1.88/1.60
    9770716 63 421 HO,64 GTO 65 D-Port 1.92/1.66
    9771980 63 421 SD 64 D-Port 2.02/1.76
    77 65 GTO, 65 421 HO 65 D-Port INTAKE MANIFOLD BOLT PATTERN IS THE SAME FOR ALL 65-79 HEADS.
    093 66 389 GTO 65 D-Port
    670 67 400 GTO 72 D-Port
    97 LATE 67 RA GTO 65 D-Port ALL 67 & UP HEADS HAVE 2.11/1.77 VALVES UNLESS OTHERWISE NOTED
    37 EARLY 68 RA GTO 72 D-Port
    96 LATE 68 RA GTO 72 ROUND
    62 68 & 69 GTO AUTO TRANS 75 D-Port
    16 68 GTO MANUAL TRANS 72 D-Port
    17 68 350 TEMPEST 72 D-Port 1.96/1.66
    18 68 350 HO 68 D-Port 1.96/1.66
    47 68 & 69 350 AUTO TRANS 72 D-Port 1.96/1.66
    48 69 RA3 400, 350 HO 68 D-Port
    722 69 RA4 GTO FBIRD 72 ROUND TALL INTAKE PORT
    12 70 400 RA GTO FBIRD 72 D-Port
    13 70 400 GTO GP 72 D-Port
    614 70 RA4 GTO FBIRD 72 ROUND TALL INTAKE PORT
    64 70 455 HO GTO GP 87 D-Port
    96 71 400 GTO GP 96 D-Port
    66 71 455 ALL 4BBL 114+ D-Port
    191(797) 71 455 HO 108-111 ROUND TALL INTAKE PORT
    94 71 350 ALL 89 D-Port 1.96/1.66
    7K3 72 400 ALL 4BBL 96 D-Port LARGE EXHAUST CROSSOVER OPENING ON 72-79
    7M5 72 455 114 D-Port
    7F6 72 455 HO 108-11 ROUND TALL INTAKE PORT
    7H1 72 350 89 D-Port 1.96/1.77(ODD)
    46 73, 74 350 89 D-Port 1.96/1.66
    4X,4C 73, 74 400 ALL 96-111 D-Port 2.11/1.66
    16 73, 74 455 SD 108 ROUND TALL/WIDE INT PORT
    6X

    75-79 350 & 400 ALL
    75-76 455

    		 see chart below D-Port 2.11/1.66
    5C,5X,5G 75-76 455, SOME 350 93-114+ D-Port 2.11/1.66
    EDELBROCK PERFORMER RPM ALUMINUM 72 or 87 ROUNDPORT FLANGE 2.11/1.66 (1.77 optional)
    HEAD C.C.'S ARE APPROXIMATE DUE TO PRODUCTION VARIANCES


    OTHER SPECIAL CASTING INFORMATION

    YEAR OF APPLICATION ENGINE CU. IN. VALVE SIZES CASTING NUMBER ADDITIONAL STAMPING I.D. NUMBER CHAMBER VOLUME CC'S
    1975-76 400 2.11/1.66 6X 8 100.04
    1975-76 455 2.11/1.66 6X 6 124.51
    1977 350 2.11/1.66 6X 4 93.74
    1977 400/W72 2.11/1.66 6X 4 93.74
    1977 400 2.11/1.66 6X 8 100.04
    1978 400 2.11/1.66 6X 8 100.04
    1978-1979 400/W72 2.11/1.66 6X 4 93.74

    HEAD STAMP LOCATION ON PONTIAC HEADS


    CLICK IMAGE FOR LARGER VIEW
  • Pontiac Engine Specs

    Pontiac Engine Torque Specs

    Bolts or Parts Lube or Sealer Torque to:

    Main Caps

    		 Engine Oil 95 ft-lbs.

    Rear Main Cap

    		 Engine Oil

    120 ft-lbs.
    Warning!!!    If you are using ARP bolts, you must use
    their specs. 
    Connecting Rod Bolts Assembly Lube 45 ft-lbs.
    SD Connecting Rod Bolts Assembly Lube 65 ft-lbs.

    Cylinder Heads

    Engine oil

    95 ft-lbs.
    Rocker Studs (screw-in) Engine Oil 55 ft-lbs.

    Rocker Arm Nuts

    (Non-Adjustable Rockers)

    		 Assembly Lube 20 ft-lbs.
    Oil Pump Bolts Engine Oil 30 ft-lbs.
    Oil Pump Cover Bolts Engine Oil 15 ft-lbs.
    Windage Tray Engine Oil 15 ft-lbs.
    Oil Pan Engine Oil 12 ft-lbs.
    Camshaft Thrust Plate Engine Oil 15 ft-lbs.

    Cam Sprocket/Timing Gear

    (upper)

    		 Thread Locker 45 ft-lbs.
    Timing Cover to Block Engine Oil 35 ft-lbs.
    Water Pump to Cover Engine Oil  

    Single Timing Cover to

    Intake bolt

    		 Install rubber o-ring with light RTV silcone 10 ft-lbs.
    Valley Pan Bolts Engine Oil 15 ft-lbs.

    Intake Manifold
    (Cast Iron Heads)

    Intake Manifold
    (Aluminum Heads)

    		 Non- Hardening Sealer

    40 ft-lbs.
     

    25 ft-lbs.
    Valve Cover Engine Oil 8 ft-lbs.
    Exhaust Manifold Anti-Seize Lubricant 30 ft-lbs.
    Spark Plugs No Lube or Sealer 20 ft-lbs.

    Flexplate (Automatic)

    Flywheel (Clutch)

    		 Thread Locker 95 ft-lbs.
    Clutch Pressure Plate Thread Locker 25 ft-lbs.

    Centerbolt

    (Harmonic Damper)

    		 Thread Locker 160 ft-lbs.

    Bellhousing

    (Transmission to Block)

    		 Engine Oil 40 ft-lbs.

     

    PONTIAC ENGINE CHART
    ENGINE BORE STROKE MAIN DIA.
    326 CU. IN. Stock Bore 3.720 3.750 3.00
    		30 over 3.750    
    60 over 3.780    
    350 CU. IN. Stock Bore 3.875 3.750 3.00
    30 over 3.905    
    60 over 3.935    
    389 CU. IN. Stock Bore 4.062 3.750 3.00
    30 over 4.092    
    60 over 4.122    
    400 CU. IN. Stock Bore 4.120 3.750 3.00
    30 over 4.150    
    60 over 4.180    
    421 CU. IN. Stock Bore 4.093 4.000 3.25
    30 over 4.123    
    60 over 4.153    
    428 CU. IN. Stock Bore 4.120 4.000 3.25
    30 over 4.150    
    60 over 4.180    
    455 CU. IN. Stock Bore 4.151 4.210 3.25
    30 over 4.181    
    60 over 4.211    
    BPI ASSEMBLIES/ENGINES
    CU. IN. BORE STROKE MAIN DIA.
    461 CU. IN. BPI 4.155 4.250 3.00/3.250
    467 CU. IN. BPI 4.181 4.250 3.00/3.250
    474 CU. IN. BPI 4.211 4.250 3.00/3.250
    496 CU. IN. BPI 4.310 4.250 3.00
    505 CU. IN. BPI 4.350 4.250 3.00
    511 CU. IN. BPI 4.375 4.250 3.00
    487 CU. IN. BPI 4.155 4.500 3.00/3.250
    494 CU. IN. BPI 4.181 4.500 3.00/3.250
    501 CU. IN. BPI 4.211 4.500 3.00/3.250
    525 CU. IN. BPI 4.310 4.500 3.00
    535 CU. IN. BPI 4.350 4.500 3.00
    541 CU. IN. BPI 4.375 4.500 3.00
  • Pontiac Blocks Cu.In. Chart

    Pontiac Cu.In. Chart
    326 Block Stroke
    Bore 3.75 4.00 4.21 4.25 4.50
    Stock 3.720 326 348   370  
    +.030 3.750 331 353   376  
    +.040 3.760 333 355   378  
    +.050 3.770 335 357   380  
    +.060 3.780 337 359   382  
     
    350 Block Stroke
    Bore 3.75 4.00 4.21 4.25 4.50
    Stock 3.875 354 377   401  
    +.030 3.905 359 383   407  
    +.040 3.915 361 385   409  
    +.050 3.925 363 387   411  
    +.060 3.935 365 389   413  
     
    389 Block Stroke
    Bore 3.75 4.00 4.21 4.25 4.50
    Stock 4.062 389 415   441 467
    +.030 4.092 395 421   447 473
    +.040 4.102 396 423   449 476
    +.050 4.112 398 425   452 478
    +.060 4.122 400 427   454 480
     
    400 Block Stroke
    Bore 3.75 4.00 4.21 4.25 4.50
    Stock 4.120 400 427 449 453 480
    +.030 4.150 406 433 456 460 487
    +.035 4.155 407 434 457 461 488
    +.040 4.160 408 435 458 462 489
    +.050 4.170 410 437 460 464 492
    +.060 4.180 412 439 462 467 494
    +.065 4.185 413 440 463 468 495
     
    421 Block Stroke
    Bore 3.75 4.00 4.21 4.25 4.50
    Stock 4.093   421 443 447 474
    +.030 4.123   427 450 454 481
    +.035 4.128   428 451 455 482
    +.040 4.133   429 452 456 483
    +.050 4.143   431 454 458 485
    +.060 4.153   433 456 461 488
    +.065 4.158   435 457 462 489
     
    428 Block Stroke
    Bore 3.75 4.00 4.21 4.25 4.50
    Stock 4.120   427 449 453 480
    +.030 4.150   433 456 460 487
    +.035 4.155   434 457 461 488
    +.040 4.160   435 458 462 489
    +.050 4.170   437 460 464 492
    +.060 4.180   439 462 467 494
    +.065 4.185   440 463 468 495
     
    455 Block Stroke
    Bore 3.75 4.00 4.21 4.25 4.50
    Stock 4.151     456 460 487
    +.030 4.181     462 467 494
    +.035 4.186     464 468 495
    +.040 4.191     465 469 497
    +.050 4.201     467 471 499
    +.060 4.211     469 474 501
    +.065 4.216     470 475 503