SPECIFICATIONS FOR 1960-1979 PONTIAC HI-PERF. CYLINDER HEADS SOURCE:HTTP://WWW.OWT.COM/USERS/WALTSCH/PHEAD YEAR APPLICATION PROD. # ORIG PART # HEAD # VALVES STK. CC NHRA MIN. ---- ----------- -------- ------------ -------- -------- ------- ---------- 1960 389SD 535460 535461 535461 1.92/1.60 68 66.8 61-62 389SD,421SD 540304 540306 40306 1.92/1.66 68 66.8 62-63 389SD,421SD 544124 544127 544127 2.02/1.76 68 66.8 1963 421SD 9771983 9771980 9771980 2.02/1.76 65.6 64FX 63-64 421HO,389GTO 9770981 9770716 9770716 1.92/1.66 68 66.8-66 1965 389 9781078 9778775 75 1.92/1.66 92/68 90/68 1965 421,389GTO 9781079 9778776 76 1.92/1.66 70/68 68/65 1965 421HO 9781081 9778777 77 1.92/1.66 68 65 1966 389,421 9784209 9782092 092 1.92/1.66 70 68 1966 389GTO,421HO 9784212 9782093 093 1.92/1.66 68 65 1967 400,428 9788067 9787670,1 670 2.11/1.77 72 65 1967 400RA 9787997 9787997 97 2.11/1.77 72 65 1968 400,428 9791559 9791562 62 2.11/1.77 75/72 65 1968 400,428 9790118 9791216 2,16 2.11/1.77 72 65 1968 400RA-1 9792700 9792731 31 2.11/1.77 72 65 1968 400RA-2 9794040 9793596 96 2.11/1.77 71 65 1969 400,428 9790118 9791216 16 2.11/1.77 72 65 1969 400 9791559 9791562 62 2.11/1.77 72 65 1969 400RA-3 9795043 9795048 48 2.11/1.77 72 65 1969 400RA-4 9796721 9796722 722 2.11/1.77 71 65 1970 400RA-3 9799496 9799612 12 2.11/1.77 72 65/62 1970 400 9799497 9799613 13 2.11/1.77 72 65/62 1970 400RA-4,LS1 9799498 9799614 614 2.11/1.77 71 62 1970 455 9799362 9799364 64 2.11/1.77 87 75 1971 400 481760 481196 96 2.11/1.77 96 85.81 1971 455 483714 481766 66 2.11/1.77 114 102.8/101.8 1971 455HO(LS5) 481758 481197 197 2.11/1.77 111 98 1972 400 486316 486073 7K3 2.11/1.77 96 85.8 1972 455 494498 486075 7M5 2.11/1.77 114 101.8 1972 455HO(LS5) 485319 48670 7F6 2.11/1.77 111 98 73-74 400 494333 488534 4X 2.11/1.77 98 88.27 73-74 455 494331 488541 4X 2.11/1.77 114 102.3 1974 350GTO 494336 494346 46 1.96/1.66 89 86.2 73-74 455SD(LS2) 485214 485216 16 2.11/1.77 111 100.7 1975 400 495345 495354 5C 2.11/1.77 101 98.09 76-79 400 500801 500762 6X 2.11/1.77 101 98.09/89.06(1979)