Casting # CID Years Intake Exhaust Chamber CC Additional Comments  
6399 307 62-63          
330545 350 73         76cc - 2.02"/1.6" valves - Corvette & Camaro
330862 400 70-73         1.94"/1.5" valves
333881 350 74-75         76cc - 2.02"/1.6" valves - Corvette & Camaro
333882 350 74-80         76cc
333882 400 74-80         76cc
340292   70's         Service replacement head, 64cc
354434 262/267/305 75-79          
358741 305 76-79          
376445 305,350 80-84          
376450 262,305,350 74-81         7 bolt exhaust bolt holes - 168/60 cc port volumes
376455 350 77-85          
376495 350 70-79          
378450 305 78-85          
458642 350,400 67-70          
462624 350,400 75-86         7 bolt exhaust bolt holes
468642 350,400 76-up          
471513 267,350 79          
517513 267,350 79          
3636839 265 55          
3703523 265 55         Corvette
3713358 265 55-56          
3713569 265 55-56          
3725306 265 55-57          
3731539 283 57         Corvette w/Rochester mechanical FI
3731544 283 57-61          
3731554 283 57-62          
3731556 283 57          
3731762 265 56         Corvette 2X4
3737775 283,327 62-67          
3740997 283 57          
3743056 283 58          
3743096 327 62-67         GMC truck
3747363 283,327 57-61          
3747460 283/327 59-67          
3748770 283 58         Corvette 1X4, 2X4, & FI
3748772 283 58-61          
3755537 283 57-62          
3755539 283 58-62          
3755549 283 57-62          
3755550 283 59         Corvette
3755585 327 62-67         GMC truck
3767450 305 76-79         7 bolt exhaust
3767460 283 64-67         HD truck only
3767462 327 62-67          
3767465 283 59-61          
3767754 283 59-61         283 Power Pack
3767792 283 60-64          
3770126 327 69          
3774682 283,327 60-64          
3774684 327 62-64          
3774692 283 58-64         60-61 Corvette, 283 Power Pack
3782461 327 64-66         "Camel Hump" head, 161/62cc port volumes
3782461X   60-63         "Camel Hump" head, 172/64cc port volumes
3795896 283,327 63-65         62-64 327/350hp Corvette, 283 Power Pack
3798996 327 63-67          
3814480 283,327 60-67          
3814482 327,350 62-67         low compression head, 75cc
3817680 283,327 63-67          
3817681 327,350 62-67          
3817682 283 61-62          
3836839 265 55          
3836842 283,327 57-67          
3837064 265,283 56-62          
3837065 265 55-56         GMC truck
3847820 283 57-58          
3876775 283,327 60-67         Camaro, 327/210hp
3884520 283,327 66-67         60cc, GM & Studebaker, some Canadian built
3890462 302,327,350 66-67         "Camel Hump" head - 161/65cc port volumes
3901068 350 87-up         Goodwrench crate engine, 350/285hp, 64cc, 72 bolt angle
3911032 307,327 68          
3912264 283 58-62        
3912265 283 63-64          
3912311 327 67        
3912313 327 65-67          
3917290 307,327 67-68        
3917291 302,327,350 67-68         "Camel Hump" head, 161/65cc port volumes
3917292 327 68         "Camel Hump" head, Corvette 327/350hp
3917293 307,327 68         75cc
3927185 307,327 69-70         69cc
3927186 302-350 69-70         "Camel Hump" head, 63cc
3927187 350 69-70         "Camel Hump" head
3927188 307 69-70         74cc
3928455 302,327 68        
3928494 327,350 68          
3928495 327 68        
3931633 307 68-73          
3931635 350 68-76        
3931637 327 68-69          
3931638 327 68         GMC truck
3932441 350 69-70         76cc, 161/65cc port volumes
3932441X 350,400 69-70         350- 80cc, 1.94"/1.5" valves; 400- 1.94"/1.6" valves; 165/65cc port volumes
3932454 307 69          
3946812 350 69          
3946813 350 69-70          
3947040 327 68         64cc, GMC truck, no accessory holes, "right angle" casting
3947041 302,350 69-70         64cc, w/accessory holes, "right angle" casting
3951598 400 70         76cc
3964286 350            
3965742 350 70         Service head
3970126 327,350 67-70          
3973370 350 69-70         Service head, straight or angle plug, 1.940" x 1.500" Valves, 67CC
3973414 350 70         "Camel Hump" head, LT1, 64cc
3973487 350 71-76         71-72 LT1, 75cc, 161/65cc port volumes
3973487X 350 71-72         75cc, larger intake ports
3973493 400 71         76cc
3986316 350 71         Corvette, 76cc
3986336X 350           76cc
3986388 307,350 68-76          
3986339 307,350 71         74.5cc
3986339X 307,350 71         74.5cc
3991492 350 70         "Camel Hump" head, LT1, 64cc, straight plug
3991492   71-up         Replacement head, 64cc, straight or angle plug
3998916 350 72         LT1, 76cc, screw in studs, large valves
3998920 350 72-73          
3998991 307,350 72-73         74.5cc, hardened seats in 73
33998993 307,350 72-73         74.5cc, hardened seats in 73, 159/64cc port volumes
3998993 350           Goodwrench crate engine, Mexican made
3998997 350,400 72-73         76cc, hardened seats in 73
3998997 305,350 78-84         161/65cc port volumes
4079261 350 75          
10033687             Pontiac aluminum race head, 62cc, angle plug, 196cc ports, 2.10"/1.625" valves, 23 bolt angle
10045434             Aluminum head, 55cc, angle plug, raised runner design
10051101             Bowtie aluminum head, 55cc, raised runner design, angle plug, 196cc port volume
10088113 350 88-up         Corvette, raised runner D port exhaust, 58cc, angle plug, 1.94"/1.5" valves
10093328             Pontiac aluminum head, 15, 224/61cc volumes
10106178 350 90         Corvette ZR1 LT5, DOHC 32V passenger side
10106179 350 90         Corvette ZR1 LT5, DOHC 32V driver side
10110810 350 93-up          
10125320 350 94-96         Gen II 350, LT1, cast iron, reverse flow cooling, Impala SS, & 9C1Police Pkg.
10128374 350 92-up         Gen II 350, LT1, aluminum, 53cc, angle plug, reverse flow cooling, 175/68cc port volume
10134352             Bowtie low port aluminum head, 45cc, angle plug, 223cc port volume, 18
10134363             Bowtie high port aluminum head, 45cc, angle plug, 210cc port volume, 18
10134363             Bowtie high port aluminum head, 50cc, angle plug, 250cc port volume, 18, CNC machined, 2.15"/1.625" valves
10134363             Bowtie high port aluminum head, 60cc, angle plug, 215cc port volume, 18
10134363             Bowtie high port aluminum head, 65cc, angle plug, 18
10134363             Bowtie high port aluminum head, 35-37cc, 223cc port volume
10147898 350 95-96         Goodwrench crate engine
10174389 350 91-94         Corvette ZR1 LT5, DOHC 32V driver side
10174390 350 91-95         Corvette ZR1 LT5, DOHC 32V passenger side
10185040             Aluminum head, 1st version, 45cc, angle plug, splayed valve, 263cc port volume
10185040             Aluminum head, 2nd version, 45cc, angle plug, splayed valve, 240cc port volume
10205245 350 93         Gen II 350, LT1, aluminum head, reverse flow cooling, 175/68cc port volume
10207643 350 94-96         Gen II 350, LT1, aluminum head, reverse flow cooling
10225121 350 94-95         Corvette ZR1 LT5, DOHC 32V driver side
10225122 350 94-95         Corvette ZR1 LT5, DOHC 32V passenger side
10239902 350 96-up         Gen II 350, aluminum head, reverse flow cooling
10239906 350 96-up         Vortec 5700, L31, 64cc, 1.94"/1.5" valves, 170cc port volume
102480011 SB2 97-up         SB2 2nd version, mirror port, revised plug location & valve angles
12552520 305 96         Vortec 5000 truck
12554290 350 94-96         Gen II 350, LT1, cast iron, reverse flow cooling, Impala SS & 9C1 Police Pkg.
12558062 350 98         Vortec 5700
14096217 350 55-86         350/300hp crate engine, 64cc, 90 intake bolt angle
14010201 305 84          
14011034             Bowtie Phase 2 iron head, 64cc, angle plugs, 184cc port volume, 2.02"/1.6" valves
14011049             Bowtie Phase 6 aluminum head, 55cc, angle plug, 180cc ports, 2.02"/1.6" or 2.10"/1.65" valves
14011083 350 55-86         350/300hp crate engine, 64cc, 90 intake bolt angle
14014415 267,305 80-85          
14014416 305 80-85         305HO, 58cc, 1.84"/1.5" valves, 7 bolt exhaust
14014440 305 80         305HO, 58cc, 1.84"/1.5" valves
14020517 350 80          
14020555 305 81          
14020556 350 80-81          
14022056 350 81-85          
14022301 305 78-79          
14022601 267,305 80-85         305HO, 58cc, 1.84"/1.5" valves, 7 bolt exhaust
14022801 305 80-85          
14071114 350 80-85          
14079261 350 86          
14085963 350 85-86          
14089119 350 87-88          
14094093 350 80-87          
14096217 350 87-up         350/285hp crate engine, 64cc, 1.94"/1.5" valves, 72 intake bolt angle
14101081 305 87-91          
14101083 350           350/285hp or 300hp crate engine, 64cc, 1.94"/1.5" valves, 90 or 72 intake bolt angle
14101128 350 86-87         Corvette aluminum head, 58cc, angle plug
14102187 305 87-91         305HO, 1.85"/1.5" valves, 58cc, 7 bolt exhaust
14102191 305,350 87-up         7 bolt exhaust
14102193 305,350 87-up         7 bolt exhaust
14022301 305 80-84          
14022601 267,305 79-85          
14022801 305 80-86          
24502559 SB2 96-up         Bowtie SB2 aluminum 1st design, mirror port
33417369 350 90-up         Gen I Goodwrench, Mexican, 76cc, 1.94"/1.5" valves, 7 bolt exhaust, perimeter valve cover bolts, "heavy" casting
38998997 400 70-80          

Casting # CID Years Intake Exhaust Chamber CC Additional Comments
330864 396, 402, 366T, 427T, 454 Truck 68-84 2.06 1.72 Open    
330865 396, 402, 366T, 427T, 454 Truck 68-76 2.06 1.72 Open    
330866 366T, 427 68-78     Open    
330867 427 69-73     Open    
336765 427T 68-78 2.06 1.72 Open    
336768 427T 73-76     Open    
336781 454 73-84 2.06 1.72 Open 118 256/114cc ports
343771 366T, 427T, 454 68-86 2.06 1.72 Open    
343772 366T, 427T, 454 68-86 2.06 1.72 Open    
343783 454 70-76 2.06 1.72 Open    
346236 454 75-87 2.06 1.72 Open 120 225/116cc ports
348238 454 75-83 2.06 1.72 Open    
352625 454 70-76     Open    
353049 396, 402, 454 73-84 2.06 1.72 Open 122 255/119cc ports
366765 427T 74-78     Open    
370696 396, 454 65-78     --    
386781 454 73-79     Open    
473328 366T 68-89 2.06 1.72 Open    
3846206 396 65-70     Closed 97  
3856206 396, 402, 427T, 454, 366T 65-83 2.06 1.72 Closed 97  
3856213 366T, 427T 65-82 2.06 1.72 Closed    
3856260 396 68     Closed    
3872702 396 & 427 65-66 2.06 1.72 Closed 98  
3876875 427T 77-85 2.06 1.72 Open    
3904390 396 & 427 65-67 2.06 1.72 Closed 98  
3904393 366T 68-76 2.06 1.72 Open    
3908952 427 67     Open   "M.Truck", Marine
3909802 396 & 427 65-67 2.06 1.72 Closed 101  
3917215 396 & 427 65-69 2.06 1.72 Closed 101  
3917219 366T, 396, 427T 66-76 2.06 1.72 Closed    
3931063 396 & 427 65-72 2.06 1.72 Closed 101  
3933148 69 396/265hp, 366T, 396, 427T 69-76 2.06 1.72 Closed 112  
3933149 427T 68-76 2.06 1.72 Open 122  
3935401 427T 67-76     Open    
3937734 396 69     Open    
3964280 427 & 454 66-70 2.06 1.72 Closed    
3964290 396, 402, 427, 454 69-76 2.06 1.72 Closed 101 454 Big Oval Port
3965198 396 & 402 68-72 2.06 1.72 Closed    
3969854 396 & 402 68-72     Closed    
3973195 402 71-76     Open    
3975950 366T, 396, 402, 427T 69-77 2.06 1.72 Open    
3986133 366T & 454 68-84 2.06 1.72 Open    
3986135 366T & 427T 69-73     Closed    
3986136 396, 402, 427, 454 68-84 2.06 1.72 Open    
3993820 402 & 454 68-84 2.06 1.72 Open 113 , 113cc chamber, 255/114 ports, 454 Passenger and Trucks
3999241 402 & 454 70-73 2.06 1.72 Open 113  
6272290 402, 427, 454 72-73 2.06 1.72 Open    
6272292 402 & 454 70-78     Open    
10052902 427T Mk IV 96-     Open    
10101136 454 91-94 2.06 1.72 Open    
10101140 366T, 427T Gen V 91-     Closed    
10114156 Gen.V & VI 454 96-     Open 118  
10121033 454 78-88 2.06 1.72 Open    
10141279   96-     Closed 100 "Vortec 7400"
10487052 366T 77-90     Open    
12352783 454 79-93 2.06 1.72 Open    
12363391   96-     Open 110 Bowtie, Aluminum, Signature Series, fits MKIV, Gen.V, Gen.VI,
12558162 496 01-     Closed   Gen.VII,"Vortec 8100", 8.1L, truck
12560241   98-     Closed 100 "Vortec 7400"
12562932   91-95     Open 118 Gen.V, truck crate motor
14025175 454 83-93 2.06 1.72 Open    
14081044 454 86-90 2.06 1.72 Open    
14081045 454 78-87     Open    
14081052 366T, 427T, 454 85-87     Open    
14092359 366T & 427T Hi Perf 86-90 2.06 1.72 Open    
14092360 454 78-90 2.06 1.72 Open   Truck
14101398 454 86-90 2.06 1.72 Open    
*1 T = Tall Deck Block
Casting # CID Years Intake Exhaust Chamber CC Additional Comments
3804391 396 - 375 and 425HP 65     Closed    
3830817 409 65 2.06 1.72 Closed    
3852583 409 63-65 2.19 1.72 Closed    
3856208 396/425hp / 396/375hp 65-67 2.19 1.72 Closed 109 "Z-16" Chevelle
3873858 396 & 427 Hi Perf 65-66 2.19 1.72 or 1.88 Closed 109  
3904391 396 & 427 Hi Perf 65-67 2.19 1.72 or 1.88 Closed 107  
3904392 Aluminum 427 - 430 & 435 HP 67 2.19 1.72 Closed 107  
3919328 Aluminum 427 - 425 & 435 HP 67     Closed    
3919391 427 / 425 HP 66     Closed    
3919838 Aluminum 427 L-88 & L-89 67-69     Closed    
3919839 396 & 427 Hi Perf 67-69     Closed    
3919840 396 & 427 Hi Perf 65-69 2.19 1.72 or 1.88 Closed 107  
3919842 396 & 427 Aluminum L-88 67-69 2.19 1.88 or 1.84 Closed 107  
3931068 427 Hi Perf 66-69     Closed    
3946074 69 427 L88, ZL1, Aluminum & 71 454 LS6 69-71 2.19 1.88 Open 118  
3964291 396, 402, 427, 454 69-70 2.19 1.88 Closed 109  
3964292 454 / 450 HP 70 2.19 1.88 Closed    
3994025 454 71 2.19 1.88 Open    
3994026 454 LS-6 - 425 HP, 71 2.19 1.88 Open 118  
3996074 454 71     Open    
6258723 454 / 425 HP 71 2.19 1.88 Open    
6272990 454 70-76 2.19 1.88 Open 118 service replacement, used on some MKIV crate engines
10045427   90-     Open 91 Pontiac/Chevy Aluminum, Large Port, race
10049875   90-     Open   Pontiac/Chevy Aluminum Small port, race
10051128   88 2.19 1.88 Open 72 Bowtie, Aluminum, Symmetrical ports
10051129   88     Open   Bowtie, Aluminum "raw" casting, Symmetrical port
12363401   96-     Open 118 Bowtie, Aluminum, Signature Series, fits MKIV, Gen.V, Gen.VI
12363861   96-     Open   Signatures Series, 2ND Design, Raised Port, Aluminum
12562934 Gen.VI 502 Marine 00-     Open    
14011077 427 & 454 Solid 69-71 2.19 1.88 Open   Aluminum, fits MKIV, "C-port" 118cc chamber, also sold as a "solid" head
14044861   84-96 2.19 1.88 Open 105 Bowtie, Aluminum, MkIV, "raised runners", 1st design
14044861   96- 2.19 1.88   115 Bowtie, Aluminum, Signature Series, fits MKIV, Gen.V, Gen.VI "raised runners", 2nd design
14044861   84-96 2.19 1.88     Bowtie, Aluminum, MkIV "raw" casting of "861" MKIV 1st design
14044862   84         Aluminum Bowtie Raised Ports, 1ST Design
14096188   70-71 2.19 1.88 Open 116 54 service replacement, also used on later Mark IV LS-6, LS-7 and 454 HO crate motors
14097088 454HO & 502HO Gen V 91- 2.19 1.88 Open 118  
24502585   97         Olds/Chevy, DRCE 2, Pro Stock aluminum, for blocks w/4.900" bore centers

Tommy Ledberg