HEAD CASTING NUMBERS FOR 1964-74 PONTIAC V-8. * NEXT TO CID DENOTES ROUND PORTS. * 1964 * CID HORSEPOWER CASTING NUMBER(S) -------------------------------------------- 326 250 9773345, 845 326 280 9773395 389 215-235 543796 389 267-306 9773845, 9773345, 845 389 325-348 9770716 421 320 9773845, 9773345, 845 421 350,370 9770716 * 1965 * -------------------------------------------- 326 250 62 326 285 22 389 256 75 389 290-333 76, 9778775 389 338 77, 9778775 389 330-360 77, 9778775 421 338 76, 9778775 421 356,376 77, 9778775 * ALL CASTING NUMBERS ON END PORT * * 1966 * -------------------------------------------- 230 165 9782005 230 207 9782229 326 250 094 326 285 095 389 256 091 389 290-333 092 389 335,360 093 (GTO) 421 338-350 092 421 356,376 093 * 1967 * ------------------------------------------- 230 165 9778692 230 215 9778693 326 250 140 326 285 141 400 255-265 9778775, 142 400 325-333 9787670, 143, 061 (FB w/o RAM-AIR) 400 325-333 143, 061 400 325 9787670, 997 (FB w/RAM-AIR) 400 325-360 9787670, 997, 670 (TEMPEST/GTO) 400 325-360 670, 97, 997 (RAM-AIR) 400 290 143, 061 400 290-350 9786142, 061 (Ex GP w/4BBL) 400 350 9787671, 187, 670 (GP w/4BBL) 428 360-376 9787670, 187, 9787671 * 1968 * ------------------------------------------- 250 175 9791194 250 215 9791195 350 265 17 350 320 18 400 265 14 400 290-340 15, 215 (PONTIAC ONLY) 400 350 16, 216, 62 400 330 16, 216, 62 (FIREBIRD) 400 330-360 16, 216, 62 (NON RAM-AIR) 400 335,360 31 (MAY APPEAR AS 37) (RAM-AIR I) 400* 340,366 9793596, (R-96-A) (RAM-AIR II) 428 375 16, 216, 62 428 390 64, 9791216, (16, 216, 62) * 1969 * ------------------------------------------- 250 175 9795456 250 230 9795457 350 265 47 350 325 48 400 265 9795045, 14, 45 400 290 9795046, 15, 46 400 330-366 16, 62, 48 400 340 9795046, 15 (GP ONLY), 16, 62 400 350 62, 216 400 366 9795048 (RAM-AIR III w/MT) 400 366 9791216 (RAM-AIR III w/AT) 400* 345-370 9796722, 722 (RAM-AIR IV) 400* 375 44 (RAM-AIR V) 400 265 9799611 400 290 9799616 400 330 9799612 (FB w/MT) 400 375 44 (RAM-AIR V) ** 428 360 16 (SMALL VALVE) 428 370 62 428 360 216 (MT ONLY) 428 360 46, 216 (AT ONLY) 428 370 216 (GP ONLY) 428 390 16, 62 428 390 9795048 (MT ONLY) 428 390 9791216 (AT ONLY) 428 390 9795048 (GP ONLY) * 1970 * ------------------------------------------- 400 330 9799613 (FB w/AT) 400 330 9799616 (ALL EXC ABOVE) 400 345,366 9799612 (RAM-AIR III) 400 350 9799612 (GTO/TEMPEST w/MT) 400 350 9799613 (ALL OTHERS w/AT OR MT) 400 370 9799614 (RAM-AIR IV) 455 360 9799615 (BIG PONTIAC w/AT) 455 360 9799364 (ALL) 455 370 9799364 (455 HO) * 1971 * ------------------------------------------- 400 265 481199 400 300 481196 455 280 481198 455 325 481776, 66 455 335 481197 (MAY APPEAR AS 191)(455 HO) *NOTE: 1972 AND LATER HEADS MAY HAVE A LETTER BETWEEN THE TWO NUMBERS OF THE CASTING NUMBERS. * 1972 * ------------------------------------------- 400 200 486072 400 250 486073 (APPEARS AS 7K3) 455 200 486074 455 250 486076 (APPEARS AS 7M5) 455 300 486076 (APPEARS AS 7F6)(455 HO) * 1973 * ------------------------------------------- 400 170,185 488544, 494344, 494348 (MAY APPEAR AS 4X) 400 200,230 491347 (GP ONLY, APPEARS AS 4X) 400 200,230 488543 (ALL EXC GP, APPEARS AS 4X) 455 215,250 488541, 494341 (APPEARS AS 4X) 455 290 485216 (455 SD) ------------------------------------------------------------------------------ * 1974 * ------------------------------------------- 350 NA 494345, 494346 400 175,190 494344, 494348 (MAY APPEAR AS 4X) 400 200 494347, 494348 (APPEARS AS 4X) 400 225 494347, 494348 (w/AT, APPEARS AS 4X) 400 225 494343 (w/MT, APPEARS AS 4X) 455 215,250 494341 (APPEARS AS 4X) 455 290 485216 (455 SD) ------------------------------------------------------------------------------ * 1975 * ------------------------------------------------------------------------------- * 1976 * 350 160-165 6X, 6S 400 185 6X, 6S 455 200 6H ------------------------------------------------------------------------------- 1967-1976 PRODUCTION CYLINDER HEADS -1967- THIS WAS THE FIRST YEAR FOR LARGE VALVE HEADS. THE INTAKE VALVE AREA WAS INCREASED BY 21%, THE EXHAUST VALVE AREA BY 14%, THE VALVE ANGLE CHANGED FROM 17 deg. TO 14 deg., THE ENTIRELY NEW PORT CASTINGS WERE USED. HOWEVER, THE "CLOSED" COMBUSTION CHAMBER DESIGN WAS CONTINUED FROM PREVIOUS YEARS. THESE HEAD CASTINGS ALSO INCORPERATED PASSAGES ALONG THE LENGTH OF THE HEAD FOR THE A.I.R. PUMP WITH CORRESPONDING JETS IN THE EXHAUST PORTS. THERE ARE TWO PERFORMANCE HEADS OF INTEREST FOR 1967. THE FIRST WAS USED ON ALL STANDARD GTO AND GRAND PRIX ENGINES AND THE 428 HO. IT HAS A CASTING NUMBER 670 ON TOP OF THE CENTER TWO EXHAUST PORTS. THE SECOND HEAD WAS USED ON LATE 1967 RAM AIR ENGINES. IT IS THE EXACT SAME CASTING AS THE 670 HEAD, BUT THE CASTING NUMBER HAS BEEN RESTAMPED 97. THE DIFFERENCE BETWEEN THE HEADS ARE ENTIRELY IN THE MACHINING OF THE SPRING SEATS AND THE VALVES USED. THE 670 HEAD IS MACHINED FOR A SPRING HEIGHT OF 1.586" WHILE THE 97 HEAD IS MACHINED FOR 1.719" INSTALLED HEIGHT TO CORRECT VALVE SPRING BREAKAGE TENDENCY OF THE 670 HEAD WHEN USING RAM AIR SPRINGS THE 670 HEAD USED STANDARD TYPE FLAT VALVES, WHEREAS THE 97 HEAD USED SWIRL POLISHED FLAT VALVES. EITHER OF THESE HEADS IS SUPERIOR TO ANY *PRIOR* PONTIAC HEAD EXCEPT 1962-63 SD. -1968- PONTIAC WAS ABLE TO DISCONTINUE USE OF THE A.I.R. PUMP BY REDESIGNING THIER COMBUSTION CHAMBER. THE NEW "OPEN" CHAMBER DESIGN HAD SUPERIOR FLAME PROPAGATION, LESS QUENCH AREA, AND A LESSER SURFACE-TO-VOLUME RATIO THAN THE 1967 AND PRIOR "CLOSED" CHAMBER DESIGNS. THE INTAKE AND EXHAUST CASTINGS WERE THE SAME AS BEFORE, BUT THE EXHAUSTS USED A SLIGHTLY SMALLER A.I.R. BOSS ALTHOUGH THE PASSAGES WERE NOT DRILLED. IN EARLY 1968, THE PERFORMANCE HEADS TO USE WERE THE RA-1 (#37), THE GTO AND 428 HO HEADS(#16), AND THE GRAND PRIX 400 AND PONTIAC 428(#62). THE RA-1 USED FLAT, SWIRL POLISHED VALVES WHILE THE STANDARD HEADS USED REGULAR VALVES. IN MID-1968 PONTIAC REDESIGNED THE EXHAUST PORT TO A ROUND CONFIGURATION AT THE EXHAUST MANIFOLD FLANGE. THE INTAKE PORT WAS LEFT UNCHANGED, ALTHOUGH, A STEEPER, TULIPED, AND SWIRL POLISHED VALVE 9 GRAMS LIGHTER THAN THE STANDARD WAS USED. THE SPRING SEATS WERE MACHINED FOR A 1.812" INSTALLED HEIGHT AND THE PUSHROD GUIDE HOLE IN THE HEAD WAS ENLARGED TO ACCOMMODATE LARGER DIAMETER PUSHRODS. THE COMBUSTION CHAMBER WAS ADDITIONALLY MACHINED TO A MORE "OPEN" CONFIGURATION WHICH ALSO REDUCED PISTON TO VALVE CLEARANCE. THESE NEW RA-2 HEADS CARRIED CASTING NUMBER 96. -1969- PONTIAC CONTINUED THIER STANDARD HEADS ESSENTIALLY UNCHANGED. THE STANDARD GTO HEAD WAS THE SAME AS 1968 #16. THE RA-3 AND 400 HO "D-PORT" HEAD (#48), WAS NEARLY A STANDARD GTO HEAD USING THE RA-4 COMBUSTION CHAMBER DESIGN FOR INCREASED HORSEPOWER. THE #48 HEADS USED THE STANDARD INTAKE MANIFOLD AND STANDARD FLAT, UNPOLISHED VALVES ALSO. THE 1969 RA-4 HEAD (#722), RECIEVED A REDESIGNED INTAKE PORT WHICH RAISED THE PORT ROOF BY 5%. THE PORT WAS RAISED PRIMARILY TO INCREASE THE HIGH VALVE LIFT AIR FLOW. ADDITIONAL VALVE LIFT WAS GAINED BY USING 1.65 RATIO ROCKER ARMS. -1970- THE GTO(#13), RA-3(#12), AND RA-4(#614) HEADS REMAINED ESSENTIALLY UNCHANGED FRIM THE PRIOR YEAR, BUT THE COMBUSTION CHAMBER VOLUME WAS INCREASED BY 3cc TO REDUCE THE COMPRESSION RATIO FROM 10.75:1 TO 10.50:1. A NEW HEAD WAS INTRODUCED FOR THE 455 HO(#64). IT WAS ESSENTIALLY A RA-3 HEAD WITH A LARGER 87cc COMBUSTION CHAMBER SO AS TO ACHIEVE 10.25:1 COMPRESSION RATIO WITH A 455. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX ---------- ALSO SEE NEXT SOURCE BELOW ------------ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 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)