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SBC Head Casting Numbers

Head casting numbers and the head casting date are located under the valve covers, in the rocker arm valley.

Number Year Engine Valves Details
10033867       Over the counter Pontiac 23' head, 62cc, angle plug, 196cc intake port, aluminum
10045434       55cc, angle plug, raised runner, aluminum,roll over head
10051101       Bowtie, aluminum, 55cc, angle plug, raised runner, 196cc intake port
10088113 88-up 350   D port exhaust, 1.94/1.5 valves
10093328       Over the counter, Pontiac 15' head, aluminum,224cc ports, 61cc chambers, roll over head
10106178 90 350   LT5, ZR1, DOHC, 32-valve, pass. side, aluminum
10106179 90 350   LT5, ZR1, DOHC, 32-valve, drvs. side, aluminum
10110810 93-up 350    
10125320 94-96 350   on 9C1 Police package, Impala SS, Cadillac Fleetwood, Buick Roadmaster, reverse flow cooling
10128374 92-up 350   aluminum, reverse flow cooling, 175/68cc ports
10134352       Bowtie, 45cc, angle plug, low port, 223cc intake port, aluminum, 18' race head
10134363       This block number has been used in many different versions of this aluminum 18 deg and 15 deg Bowtie race head. Different chamber volumes, port volumes, port locations, valve sizes, etc. were used. Check this castingcarefully to determine which features it may have. There are at least 6 different versions as of 11/99.
10147898 95-96 350    
10174389 91-94 350   drvs. side, aluminum
10174390 91-95 350   pass. side, aluminum
10185040       Bowtie, aluminum, 45cc chambers, 1st version, symmetrical ports, 263cc intake ports, splayed valves
10185040       Bowtie, aluminum, 45cc chambers, 2nd version, symmetrical ports, 240cc intake ports, splayed valves
10205245 93 350   Gen.II LT1, aluminum, reverse, flow cooling, 175/68cc port volumes
10207643 94-96 350    
10215339 97 350   Gen.III,LS1, aluminum
10225121 94-95 350   drvs. side, aluminum
10225122 95 350   LT5, ZR1, DOHC, 32-valve, pass. side, aluminum
10239902 96-up 350   Reverse flow cooling, 195cc port, 54.4cc chamber, angle plug
10239906 96-up 350   170cc intake port, 1.94/1.5 valves
12367713 99-up     Fast Burn used on ZZ430 crate motor, aluminum, 210cc intake port, 2.00/1.55 valves, 62cc chamber
12480005 2000     LS1GTZ, aluminum, 38cc, 2.125/1.625 valves, angle plug
12480011 97-up     Bowtie SB2.2, aluminum, 2nd version of SB2, 48cc chambers, mirror ports, revised valve angles and plug location
12551561 96 350   Gen.II,LT1, aluminum
12552520 97-up 305    
12554290 94-96 350   on 9C1 Police package, Impala SS, Cadillac Fleetwood, Buick Roadmaster, reverse flow cooling
12555690 96 350   Gen.II,LT4, aluminum
12558059 97 305   Vortec, truck, 1.84/1.5 valves, 64cc chamber
12558062 98 350   L31 Vortec, truck, 64cc chambers, 1.94/1.5, 170cc intake port
12558806 97-98 350    
12559853 99 350   Gen.III,LS1, aluminum
14010201 84 305    
14011034 80 350 2.02 / 1.6 Bowtie, cast iron, 64cc chambers, 184cc port volume, angle plug, Phase II head
14011049 82 350 2.02 / 1.6 Bowtie, aluminum, 55cc chambers, angle plug, 180cc ports, Phase 6
14011083 55-86 350 1.94/1.5 285/300hp
14014415 80-85 267 - 305    
14014416 80-86 267 - 305 - 350 1.84/1.5  
14014440 80 305 1.84/1.5  
14020516 80 350    
14020517 80 350    
14020555 81 305 - 350    
14020556 81 350    
14020556 81-85 350    
14022601 79-86 267 - 305 1.71 / 1.5 58cc chambers
14022801 80-86 305 1.71 / 1.5  
14034808 96-up 350    
14071114 80-85 350    
14079261 86 350    
14085963 86 350    
14089119 86-88 350    
14094093 86-88 350    
14094093 86-88 350    
14096217 55-86 350   72' or 90' center intake manifold bolt angles
14101081 87-91 305    
14101083 87-up 350   chambers, 72' center manifold bolt angles
14101128 86-87 350    
14102187 87-91 305 1.84/1.5  
14102188 88- 93 350 centerbolt    
14102191 87-up 305 - 350    
14102193 87-up 305 - 350    
176450 75-76 262 - 305 1.71 / 1.5  
1816887 63 283   Made in Canada, GMC HD truck
24502559 96-97     Bowtie,SB2, 1st version, mirror ports, aluminum, 196cc port, CNC version 280cc port, 38cc chamber
25500141       Buick/Chevy aluminum 10' head, 42cc chambers, symmetrical ports, 235cc intake port volumes, 2.1/1.625 valves
3030817 74 400   2-bolt
3238882 68-69 350    
3297185 57-67 307 - 237 - 350    
330545 71-75 350 1.94 / 1.5, 2.02/1.60 245, 250 hp
330862 71-73 400 1.94 / 1.5  
333881 71-76 350   165, 270 hp
333881 74-75 350 2.02/1.60 76cc,
333882 70-80 307 - 327 -350 -400 1.94 / 1.5 76cc CFM Inlet 137.5 / Exh 95.4
33417369 90-up 350   Hecho en Mexico, 76cc
3391635 68-76 305    
340292 73-80 350 2.02 / 1.6 Over the counter, angle plug, 64cc
354434 75-76
76-79
262
305
1.71 / 1.5  
358741 71-79 262 - 305 1.71 / 1.5  
3636839 55 ?? 59 265    
367450 75-76 262    
3703523 55 265    
3703524 55 265    
3713358 55-56 265   truck
3713569 55-56 265   truck
3720991 56-57 265    
3725306 56 -57 265   corvette
3727185 69-73 307    
3731262 56 265   corvette 2 x 4 brl
3731539 57-66 283    
3731544 55-61 265 - 283    
3731548 57-62 283    
3731554 57
58-62
283
283
 
3731556 57 283   truck, Made in Canada
3731762 56 265   Corvette 2 x 4 brl
3737465 60-61 283    
3737739 57-62 283   283 and 283 Corvette F.I.
3737775 62-67 283 - 327    
3740997 57 283   1x4, 2x4 and FI (exc.-283hp)
3743056 58 283   truck
3743096 62-67 327   GMC truck
3747363 57-62 265 - 327   truck
3747460 59-67 283 - 327    
3748720 57-58 283   1x4 or 2x4 bbl carb or F.I Corvette
3748770 55-61
58-62
57
265-283
283
283
   
3748772 57-62 283    
3755537 57-62 283   2 brl
3755538 59 283   corvette FI
3755539 58-62 283   truck
3755549 57-62 283   Car and truck
3755550 57-62 283   corvette FI
3755585 62-67 327   GMC truck
3756519 57-62 283   283 and 283 Corvette F.I.
3760116 59 283   1x4 bbl carb or F.I. Corvette
376445 80-84 350 1.71 / 1.5 truck
376450 75-81 262 - 267 - 305   6 or 7 exhaust bolt holes
376455 77-85 350    
376495 69-79 350    
3767460 55-67 265 - 283 - 327    
3767462 62-67 327    
3767465 59-61 283    
3767754 59-61 283    
3767792 60-67 283   Car and truck
3770126 67-70 327 - 350    
3773012 55 265   corvette
3774682 60-67 283 - 327    
3774684 57-67 283 - 327   truck
3774684 62-64 283-327   Chev. trucks and GMC
3774690 58 283   corvette fuel injection
3774692 58-64 283   corvette
3776434 64-67 327    
3782461X 60-63 283 - 327   Camel hump, no accessory holes, slightly larger 172/64cc port volumes
3782461 61-70 302 - 307 - 327 - 350   Camel hump, no accessory holes, 160/62cc port volumes
3782462 67 327    
3782870 62-67 327   327 and 327 Corvette
3782879 62-67 327   327 and 327 Corvette
3789817 62-67 327   327 and 327 Corvette
3789935 57-62 283    
3790721 64-67 283    
3792563 65-67 327    
3795893 58-72 283 - 307 - 327    
3795896 63-72 283-307-327    
3796896 64-67 283    
3798996 63-67 327    
3814462 67 350    
3814480 60-67 283 - 327   truck, 70cc chambers, 1.72/1.5 valves
3814482 62-67 283 - 327 - 350   truck 75cc chambers
3817680 63-67 283 - 327   283 4 bbl and F.I.
3817681 62-67 327-350    
3817682 61-62 283   2 brl
3836839 55 265    
3836842 57-67 265-283-327    
3836942 58-62 283    
3837063 58-62 283    
3837064 56-62 265 - 283    
3837065 55-56 265   truck
3837739 57 283   283 and 283 truck
3837775 62-67 283 - 327    
383882 71-73 400    
3848720 57-58 283   truck
3849820 65 327    
3849852 57-67 283    
3849935 65-67 283    
3852172 62-64 327    
3854520 62-67 283 - 327    
3855961 68-76 350   2-bolt
3858174 65-67 327    
3864812 57-67 283   283 and 283 truck
3867802 57-60 283   corvette Fuel Injection
3873064 56-57 265    
3876132 62-67 327   327 and 327 Corvette
3876487 71-73 350    
3876775 57-67 283 - 327   truck
3878775 64-67 327   truck
3884520 60-67 283 - 327   Some marked Made in Canada, 60cc chamber, also used by Studebaker
3890462 62-68 302 - 327 - 350 1.94 / 1.5 or 2.02 / 1.6 Camel hump, no accessory holes
3891492 64-67 327    
3892657 65-67 327    
3896944 65-67 283    
Number Year Engine Valves Details
3901068 87-up 350   Crate motor, 285hp, 64cc chamber
3911011 68 32    
3911032 68-70 307 - 327   truck
3912264 58-62 283   283 car and truck
3912265 63-64 283    
3912291 68-70 302 - 327 - 350    
3912311 65-67 327 - 350    
3912313 65-73 327    
3914636 68-73 307    
3914660 68-69 327   327 and 327 Corvette
3914678 68-69 327   327 and 327 Corvette
3917264 67 302   Z28 Camaro
3917290 67-70 307-327 1.71 / 1.5  
3917291 68-69
67-70
327-350
302-327
1.94 / 1.5 Camel hump, no accessory holes
3917292 67-68 327 - 350   Camel hump
3917293 68-69 307 - 327   75cc chambers
3921175 66 327   327 (350 HP)
3923441 67-79 307 - 327 - 350 1.71 / 1.5  
3927185 68-76 307-327-350   70cc chambers
3927186 68-72 302-327-350 2.02 / 1.6 Camel hump, 64cc chambers, accessory holes
3927187 69-70 302 - 350   Camel hump, 64cc chambers, accessory holes
3927188 69 307 - 327 - 350   Light truck, 74cc chambers
3928454 68 307    
3928455 68 302-327   325 HP and 350 HP
3928494 68 327 - 350   327 hi-performance 4 bbl and 350
3928495 68 327   327 std. and 327 (250 HP)
3931633 68-73 307    
3931635 68-76 350    
3931637 68-69 327   327 and 327 Corvette
3931638 68 327   truck
3931639 68 302    
3932373 68-73 307    
3932386 68-76 327 - 350   350 4-bolt and 327 Corvette
3932388 68-76 350   2-bolt
3932441 67-79 327 - 350 1.94 / 1.5 CFM inl 152 / exh 93.2
3932441 67-72 327-350   76cc chambers
3932454 69-73 307   truck
3932454 69-79 350   truck
3932882 76 400    
3933148 68-73 350    
3941174 68 327    
3946812 69 350   truck
3946813 69-79 350   truck
3947040 68 327   Right angle casting identifier, 64cc chambers, good HP head, used in trucks, no accessory holes
3947041 68-79 327 - 350 1.94 / 1.5  
3947041 69-70 302 - 350   Right angle casting identifier, 64cc, accessory holes, good HP head
3951509 74 400   2-bolt
3951511 70-73 400   4-bolt
3951598 70-71 400   2 barrel, 76cc chambers
3956618 68-76 350   4-bolt
3958618 68-76 350   2-bolt
3961598 70-76 400    
3964286 68-77 350    
3965742 70 350   over the counter, angle plug
3970010 68-76 350   4-bolt
3970020 68-73 307    
3970126 67-79 327 - 350 1.71 / 1.5 CFM inl 148.3 / exh 87.6
3970721 64-67 283    
3971293 68-69 307 - 327    
3973195 71-73 400   truck
3973370 69-70 350    
3973414 64-70 327 - 350   LT1-370hp, Camel hump, 64cc
3973487 68-71
71
350
350
1.94 / 1.5 or 2.02 / 1.6 350 high performance
350 trucks and passenger cars
3973493 70-76 400 1.94 / 1.5 76cc, CFM inl 143 / exh 87
3981462 62-67 302-327-350    
3986316 71-72 350   76cc
3986336X   350   76cc
3986339X 71 307 - 350    
3986330 69-79 350    
3986339 68-79 307 - 350 1.71 / 1.5  
3986388 68-79 307 - 350 1.71 / 1.5 truck
3991492 68-73 327 - 350 1.94 / 1.5 or 2.02 / 1.6  
3991492 69-70 350   LT1, Camel hump, accessory holes, 64cc, straight plugs
399380 70-73 400    
3998916 72-75 350 - 400   Also used w/'72 350 LT1, big valves, screw in studs
3998920 72-75 350 1.94 / 1.5  
3998991 68-76 307-350   75cc
3998993 68-79 350 1.94 / 1.5 CFM inl 150 / exh 91
3998993 68-76 307 - 350   75cc chamber. Low performance cars and trucks
3998997 72-73
78-79
78-79
80-84
350 -- 400
305
350
350
1.94 / 1.5 All 76cc
4079261 75 350    
426424 72-82 305 - 350 - 400    
458624 69-84 350   truck
460703 78-80 350    
462614 77-79 305 - 350    
462624 78-81 350 1.94 / 1.5 Z-28 Camaro
462624 76-87 305 - 350 1.94 / 1.5 r 2.02 / 1.6  
462624 75-86 350 - 400   76cc chamber
468642 75-84 350 - 400 1.71 / 1.5  
468642 76-79
80-84
350
350
   
471513 79-81 267 - 350    
472424 76-79 305    
517513 79-81 267 - 350    
6259425 68-76 350   2-bolt
6260856 68-76 350    

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