While extensive efforts and the compilation of a number of print & internet published sources have been made to ensure this chart is correct, LOE GTO's makes no guarantees of 100% accuracy.
Year
Engine (ci.)
Cast Code
Casting #
Part #
Stud Type
Intake (in.)
Exhaust (in.)
Volume (cc)
59
389
531395
Press
1.88
1.60
68
60
389SD
535461
535461
535460
Pinned
1.92
1.60
68
60
389
536109
Press
61
195/389
538177
Press
1.92
1.66
61
389/421 SD
540306
540306
540304
Pinned
1.92
1.66
68
62
195/389
538177
Press
1.92
1.66
62
389/421 SD
540306
540306
540304
Pinned
1.92
1.66
68
62
389/421 SD
544127
544127
544124
Pinned
2.02
1.76
68
63
389
543796
Press
1.88
1.60
92
63
389/421
543797
Press
1.88
1.60
72
63
389/421 SD
544127
544127
544124
Pinned
2.02
1.76
68
63
326
548232
Press
1.88
1.60
63
389GTO/421HO
9770716
9770716
9770981
Press
1.92
1.66
68 (72)
63
421SD
9771980
9771980
9771983
Press
2.02
1.76
65
63
326
9772652
Press
1.88
1.60
64
389
543796
Press
1.88
1.60
92
64
389GTO/421HO
9770716
9770716
9770981
Press
1.92
1.66
68 (72)
64
326/389
9773345
Press
1.92
1.66
70
65
326
22
Press
1.88
1.60
60
65
326
62
Press
1.88
1.60
70
65
389
75
9778775
9781078
Press
1.92
1.66
92
65
389GTO/421
76
9778776
9781079
Press
1.92
1.66
70
65
389/421HO
77
9778777
9781081
Press
1.92
1.66 (1.60)
68
66
389
091
9782091
Press
1.92
1.66
92
66
389/421
092
9782092
9784209
Screw
1.92
1.66
70
66
389GTO/421HO
093
9782093
9784212
Screw
1.92
1.66
68
66
326
094
9782094
Press
1.92(1.88)
1.66(1.60)
68
66
326
095
9782095
Press
1.88
1.60
67
400
061
2.11
1.77
72
67
326
140
9786140
1.92
1.66
67
326
141
9786141
1.92
1.66
67
400
142
9786142
1.92
1.66
90
67
400
143
9786143
Press
1.92
1.66
75
67
400/428
670
9787670
9788067
Screw
2.11
1.77
72
67
400 RA
997
9787997
9787997
Screw
2.11
1.77
72
68
400
14
9791214
9792266
Press
1.96
1.66
90
68
400
15
9791215
Press
1.96
1.66
75
68
400/428
16
9791216
9790118
Screw
2.11
1.77
72
68
350
17
9791217
Press
1.96
1.66
72
68
350 HO
18
9791218
Press
1.96
1.66
64
68
400 RA I
31
9792731
9792700
Screw
2.11
1.77
72
68
400/428
62
9790062
9791559
Screw
2.11
1.77
75 (72)
68
400 RA II
96
9793596
9794040
Screw
2.11
1.77
71
69
400/428
16
9791216
9790118
Screw
2.11
1.77
72
*NOTE: Some books show #16 used in 69, but this may
be totally incorrect. Concours guys - dont risk it!
69
400
45
Press
1.96
1.66
94
69
400/428
46
1.96
1.66
68
69
350
47
Press
1.96
1.66
72
69
400 RA III
48
9795048
9795043
Screw
2.11
1.77
72
69
350 HO
48
9795048
Screw
2.11
1.77
64
69
400
62
9791562
9791559
Screw
2.11
1.77
72
69
400 RA IV
722
9796721
9796722
Screw
2.11
1.77
71
70
350/400
11
9799611
1.96
1.77 (1.66)
80
70
400 RA III
12
9799612
9799496
Screw
2.11
1.77
72
70
400
13
9799613
9799497
Screw
2.11
1.77
75
70
455
15
9799615
1.96
1.66
87
70
400
16
9799616
478102
Press
1.96
1.66
78
70
400 RA IV
614
9799614
9799498
Screw
2.11
1.77
71
70
455
64
9799364
9799362
Screw
2.11
1.77
87
71
455 HO
197
481197
481758
Screw
2.11
1.77
111
71
455
66
481766
483714
Screw
2.11
1.77
114
71
350
94
1.96
1.66
90 (96)
71
400
96
481196
481760
Screw
2.11
1.77
96
71
455
98
1.96
1.66
114
71
400
99
1.96
1.66
96
72
455 HO
7F6
486076
485319
2.11
1.77
111
72
350
7H1
1.96
1.77 (1.66)
80
72
400
7J2
1.96
1.77 (1.66)
96
72
400
7K3
486073
486316
Screw
2.11
1.77
96
72
455
7L4
2.11
1.77
114
72
455
7M5
486075
494498
2.11
1.77
114
73
455SD
16
485216
485214
Screw
2.11
1.77
111
73
350
46
Press
1.96
1.66
89
73
350
4C
494442
Press
1.96
1.66
89
73
400
4C
494449
Press
1.96
1.66
98
73
455
4X (1H)
488541
494331
Press
2.11
1.66
114
73
400
4X (3H)
488543
494333
Press
2.11
1.66
98
73
400
4X (4H)
488544
Press
1.96
1.66
98
73
400
4X (7H)
491347
Screw
2.11
1.66
98
*NOTE: All 73 heads went to Screw-In Studs beginning
with castings dated around May 7, 1973.