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Engine Summary | Engine RPO | Engine Blocks | Cylinder Heads | SBC Factory Cams | Crankshafts | Pistons |
Intake Manifolds | Exhaust Manifolds | Balancer/Flywheel Info | Small Block Suffix Codes

General Information & Notes
Body Styles:
A = Chevelle/El Camino , B = Caprice (Full Size), G = Monte Carlo, F = Camaro, H = Vega/Monza
C/K = TRUCK, X = Nova/Chevy II, Y = Corvette
Click here for more information on body types/styles.

Small Block Chevy Crankshafts

All crankshafts have a casting number located on one of the rough finished throws or counterweights towards the front of the crank.

Two types of crankshafts are offered, cast nodular iron and forged steel. Since forged cranks are more expensive to produce, they are generally used only in high performance or severe duty (truck) applications.

Forged crankshafts are easily identified vs cast because a forged crank will have a wide parting line running down the length of the crank, while the cast crank has a thin parting line. Some forged cranks are tufftrided, which is a chemical heat treating process that hardens the bearing journal surfaces. When a crank is tufftrided it will have a dull grey color to it. Many cranks used in severe applications are cross-drilled, which helps ensure constant oiling to the main bearings. All tufftrided cranks are cross-drilled. Not all cross-drilled cranks are tufftrided.

Rear Main Seal
Beginning in 1986 all production small block chevy engines used a 1 piece rear main seal. This means the bolt pattern on the end of the crankshaft was reduced to 3.00".

Journal Size
Journal sizes were increased in 1968.

  Rod Main Displacments
Small Journal2.00"2.30" 265, 283, 302, 327
Large Journal2.10"2.450"262, 267, 302, 305, 307, 327, 350
400 Crank2.10"2.650" 400

Small Block Chevy Crank Stroke

262 ci 3.100"   305 ci 3.484"
         
265 ci 3.000"   307 ci 3.250"
267 ci 3.484"   327 ci 3.250"
283 ci 3.000"   350 ci 3.484"
302 ci 3.000"   400 ci 3.750"

Small Block Chevy Crankshaft Casting Numbers

YearsCastingCIDMaterialJournalRmain Seal Applications
1968-731130307,327castlargetwo all
1968-761181350castlarge twoall
2680327steelsmalltwo
2690350steeltwo
1968-693279302forgedlargetwoZ-28
1962-674577327forgedsmalltwo-
1968-734672307,327castlargetwo -
1975-85310514350 -largetwo-
330550350 steeltwo
1975-76354431262 castlargetwo Monza,Nova
1955-673727449265,283forgedsmalltwo-
3729449265steeltwo
1962-673734627327 forged smalltwo-
1955-673735236265,283forgedsmalltwo-
1957-633735263283 forged smalltwo-
1962-673782680327 forged smalltwo-
3814671327steelsmall two
1955-673815822265,283forgedsmalltwo-
1957-653835236283 forged smalltwo-
1956-633836266265,283forgedsmalltwo-
1963-673849847283 castsmalltwo -
1964-673876764283 castsmalltwo -
1964-673876768283 castsmalltwo -
3884577327steelsmalltwo
1967-763892690350 castlargetwo -
1968-733911001307,327castlargetwo-
3911011307,327castlargetwo
3914672327steellargetwo
3923279302steellargetwo
1969-853932442305,350castlargetwoin 1979-82 267
1968-733941174307,327castlargetwo-
1968-693941178302 forged largetwoZ-28
1969-853941182 350forgedlarge twoZ28, Vette,truck, some nitrided
3941188350steeltwo
1964-673949847283 -smalltwo
3951130327steellarge two
1970-803951529400 castXL mnstwo3.76" stroke, ext. bal.
1986-on14088526 305,350 castlargeone
1986-on14088532 350forged-one truck
1986-on14088535 305,350 castlargeoneall
86-8814088552350forged one

Small Block Chevy Piston Part Numbers

GM P/N
ENGINE
CR/Chamber CCDome TypePin Type MaterialUsage
12514101
350
8.5:1/76cc Dish P Cast 350/190HP
-
9.1:1/64cc - - - 350/285HP
-
- - - - Crate motor
12361371
350
9.1:1/64cc Dish P Cast 350/300HP Crate motor
10104455
350
9.8:1/58cc Flat top P Hyper ZZZ 1St design Crate motor
10181389
350
9.8:1/58cc Flat top P Hyper ZZZ 2nd design Crate motor
12520264
350
9.1:1/64cc Flat top P Cast 350/300HP
3946876
302
11.0:1/64cc Dome F Forged '68 to '69 Z-28
3942543
350
11.0:1/64cc Dome P Forged '69 L46
474192
350
9.0:1/76cc Dish P Cast 350 L82
3989051
350
11.0:1/64cc Dome P Forged '70 LT1
14011020
350
12.5:1/64ccDomeFForged Heavy-Duty/NOTE 1
14011021
350
12.5:1/64cc DomeF Forged Heavy-Duty/NOTE 2
14011026
350
12.5:1/64ccDomeFForged Heavy-Duty/NOTE 3
14011027
350
12.5:1/64ccDomeFForged Heavy-Duty/NOTE 4

P= Pressed-on pin; F= Floating pin., Hyper = Hypereutectic
Part numbers are for standard (Std.) bore sizes.
NOTE 1: use with 5.7" rod in cylinders 2, 3, 6, 7.
NOTE 2: use with 5.7" rod in cylinders 1, 4, 5, 8.
NOTE 3: use with 6.0" rod in cylinders 2, 3, 6, 7.
NOTE 4: use with 6.0" rod in cylinders 1, 4, 5, 8.

Small Block Chevy Intake Manifold Casting Numbers

YearsCastingCIDbblsMaterialCarbApplication
1974-76 3402613504ironQ-jetA B F X/160,185,195,245,250HP
1973-81 340266305,3502iron-A B F G
1982-85 340281305,3504ironQ-jet B F
1976-82 346249305,3504ironQ-jet all/155,165,205HP
1976-82 346250305,3504ironQ-jet all
1973-77 346260305,3502iron-A B F
1978-80 3735983052al-G
1976-82 458520305,3504al Q-jetall
1980-82 1403372305,350TTBIalcross-fire F Y
1955 37047902652iron-B
1955 37113482654iron-B Y
1956 37287252658 alWCFBY/225hp, 1st design
1986-57 3731394283 8alWCFBY/225hp, 2nd design
1957 37313982834 ironWCFB, 4jetB Y
1957 3732880265,2832iron -B
1956 37354442652iron-B
1956 37354482654iron4BBLY /210hp
1956 37371092654iron-B
1957 37396532838al-Y /245,270HP
1957 3741193283FI al-B
1957 3746826265,2832iron -B
1958-61 3746829283 4iron WCFB, QjetB Y/230hp
1962-63 3783244327 4iron WCFB, QjetB Y/250hp
1963 37941293274alAFBY 340hp
1962 37953973274ironAFB Y 340hp
1972 37977713504iron-A B F
1962-64 3799349327 4iron AFBB Y/300hp
1963-65 3826810327 FI-- Y
1956-57 3837109265,2834ironWCFB, Qjet B Y/210hp
1964-65 3840905283 2iron -A B X C K
1964-65 3844457327 4iron WCFB, QjetA B X Y/250hp, Srvc repl.
1963-65 3844459327 4iron AFBA B X Y/300hp, srvc repl.
1964-65 3844461327 4al HolleyY/350,360hp
1962-65 3866922283,3274ironQjetA B X/220hp/250hp, marine use
1966-67 3872783327 4iron HolleyA B X/275hp, w/o AIR, srvc. repl.
1966 3875954327 4iron QjetA B X/275hp, w/AIR
1965 3877652283,3272iron -A B C K,trk
1966-67 38776563274al Holley 350hp Hirise
1966 38828582834 ironQjetA B X/220hp
1966-67 38904903274alHolleyX Y/350hp hirise
1966-68 39053933274ironQ-jetA B F X/275hp
1967-68 39106013272--A F X
1969-70 3916313307,3502--all
1967-68 3917610302 4alHolleyZ-28, F, hirise
1968 3919801307,3272iron-A B C X
1967-68 3919803327,3504ironQjet A B F X Y/250,275,325,350HP
1969 3927183307,3272iron -A B F X
1969 39271843504ironQjetA B F X Y/255,300,350HP, srv. rep.
1969 39324723024alHolleyZ-28, F, Hirise
1967-69 3941126302 8alHolleyZ28 X ram (bottom) released to race teams in '67 w/o casting#
1967-69 3941130302 8alHolley Z28 X ram (top) released to race teams in '67 w/o casting#, did have Winter Foundry 'snowflake" logo.
1969-70 3958622307,3272iron
1969-70 3958626350 2iron
1971-72 3959594350 4alHolleyY, Z28, LT1, Hirise, 330/255hp
1970 39655773504ironQjetB F X/300,350hp
1970 39721103504alHolleyY, Z28, LT1 360,370hp, Hirise
1970 39721143504alZ-28, F
39721163504alHolleyhirise, service repl for '70 LT1
1971 39723613504alHolleyZ-28, F
1969-71 3973465307,3272 --A B F X
1971 39734693504 ironQjetB F Y/270hp
1969-70 3987361350 -iron-
1971 3990948350-iron-
1973 3991004350-iron-
1971 3991005307iron
1973 39977703504
1973 39977713504 ironQjetall/175,190,245,250hp
1973 3997772307-iron-
1972 6262928350- iron-
6262930-ironY
1972 6262932350 iron-
1971-72 3504iron-
1972 62637513504 ironQjetall, 175,200hp
1973 6271060350- iron
1957 7014360283FI al-
1957 7014520283FI al-
1957-58 7014800283 FIal-
1958-59 7014900283 FIal-
1958 7014960283FI al-
1959-61 7017200283 FIal
1959-60 7017250283 FIal
1959-60 7017300283 FIal
1960-61 7017310283 FIal
1960 7017320283FI al
1962 7017355327FI al
1962 7017360327FI al-
1962-63 7017375327 FIal-
1964-65 7017380327 FIal-
1979-80 14007374 3052al-
1981 14014432 350 4al-
1978-85 14057053 305,350 4alQjetPass, Camaro, Truck

Small Block Chevy Exhaust Manifold Casting Numbers

FYLYCastingCIDApplications
197376336709350 F
197375336710307,350,400 A B F G
197380346222307,350,400 A B F G
197577346247350 A B F G
197577346248350 A B F G
197680364753305,350,400 all
197082372243350 Y
197882462697267,305G
197882462698267,305G
1955-3704791265B Y
1955-3704792265B Y
1956-3725563265B Y
1956-3731557265B Y
1956-3731558265B Y
1957-3733975283B Y
1957-3733976283B Y
1965-3746563327Y
1962683747038283,327B Y
1958673747042283 B Y
1964-3747938327
1964-3747942327
1958633749965283,327B Y
1958653750556283,327B Y
1964673790729283,327Chevy II
1965-3790730283,327Chevy II
1965-3791162283,327Chevy II
1966673791182283,327B
1962633797901327 Vette
1962653797902327 Vette
1963-3797942327 Vette
1967683834947283,327B
1955-3836968265B
19553837069265Y
1964-3840715283,327A
1964683840912all A F X
1964713846559327,350Vette
1964653846563327 Vette
1964673849288283,327Chevy II
1964673849290283,327Chevy II
1964683855163283,327B C K
1966673872723283,327Chevy II
1966-3872729283,327A
1967683872730all A F
1966673872738283,327Chevy II
1966683872741283,327B
1967713872765327,350Vette
1966683872778283,307,327 B C K Y
1964673890424283,327Chevy II
1967-3892679all A F X
1967683892683all A F
1966683893604283,327B
1967-3893608all A F
1967683896956283,307,327 C K
1967683905364307,350,400 C K
1969703932376307,350A F
1970723932461350 Vette
1969703932465327,350B
1969703932469350,400B
1969703932473307,350B
1969-3932481350Y
1967-3940972350F
1969713942527302,307,350 A F X
1969703942529307,350A F X
1969-3946826302,307,350 A F X
1969-3946826302
1972733959562307,350A F
1971723973432307,350A B F X
1972743986330307,350F
1970723989036350,400B Y
1969733989041302,307,350 A F X
1970733989043307,350A B F X

Small Block Chevy Flywheel Part Numbers

Part #DIA.TeethComments
399146914"168two-piece seal, internally balanced
398639414"168400 External balance, two-piece seal
1010583214"16886-later, one-piece rear seal, ext. balance
1408572012.75"153Lightweight (15 lbs.), nodular iron, two-piece seal, int bal
1408864612.75"15386-up, Lightweight (15 lbs.), nodular iron, one-piece rear seal, ext bal
1408864814"16886-up, one-piece rear seal, ext. balance
1408865012.75"15386-up, one-piece rear seal, ext balance
10174482 89-up with six-speed m/t, requires starter (10455709)
Common clutch sizes are: 10.4", 11.0", and 11.85". Some flywheels are drilled for two different clutch patterns.


Small Block Chevy Flexplate Part Numbers

Part #DIA.TeethComments
47152912.75"153Two-piece seal blocks, int balance
47157814"168400 ext. bal, two-piece rear seal
47159814"168Two-piece seal blocks, internal balance
1012841212.75"15386-up, one-piece rear seal ext. balance
1012841314"16886-up, one-piece seal, extra thick, HD, ext bal
1012841414"16886-96, one-piece rear seal, ext. balance
1408876114"16889-up 350 HO, one-piece rear seal, ext. bal.
1408876512.75"15386-up, one-piece rear seal, ext. bal.
1408876714"16889-up 350 HO, one-piece rear seal, HD, ext. bal


Last updated: 10/20/2011
Author: MadMike Maciolek

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