Editing Identifying Chevy engines

{{Develop1}} 
==Overview==
Identifying Chevy engines isn't that difficult if all that's needed is to know whether it's a BBC or SBC, or a six or V8, etc. But to get into the finer points requires digging deeper.

==Block casting numbers and codes==
[[File:S-bbc block id.jpg|thumb|500px|Locations of Chevy V8 block ID numbers and codes]]
One of the easiest way to identify a Chevrolet engine is by the casting number (c/n) that is cast into the castings (not stamped). [[Chevy engine casting numbers]] has several sites that are useful. The Chevy V8 block casting number is generally atop the transmission mounting area of the block. The date code will usually be found in the same area, sometimes on the opposite side from the casting number, but not always. 

It is common to use just the last three numbers of the c/n when dealing with casting numbers, i.e. block c/n 10243880 would be called an "880" block. Usually the last three numbers aren't repeated but there are cases like the SBC head c/n 462 that- for some unknown reason- was reused 5 times! Fortunately this is rare.
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===SBC engine casting numbers===
{{Note1}} The Mortec site is no longer available. The Mortec casting number info is listed at the [[Identifying Chevy engines #Mortec|'''bottom of this page''']].
*[http://outintheshop.com/faq/casting/castings2.html Chevy BB and SB casting number "go-to" site] from outintheshop.com
*[http://www.nastyz28.com/sbchevy/sblock.html smallblock info] from nastyz28.com 
*[http://www.73-87.com/chevy_ids/sbcid2.htm SBC ID] from www.73-87.com
*[http://www.classictruckshop.com/castgm_smblock.asp SBC casting numbers] from classictruckshop.com
*[http://www.inliners.org/becks/BCN2.html Inline engine casting numbers] from inliners.org

===BBC casting numbers===
*[http://www.nastyz28.com/bbcmenu.php Big Block Chevy Engine Parts Identification] from nastyz28.com

==Suffix codes==
Suffix codes are stamped into a small boss on the front passenger side of the block where the head and block meet. There will sometimes be two lines of numbers and letters, later engines had just one line of numbers and letters.<br>

*[http://chevymania.com/partsid/suffix.cfm?block=Small SBC suffix code list] from Chevymania.com
*[http://chevymania.com/partsid/suffix.cfm?block=Big BBC suffix code list] from Chevymania.com
*[http://www.nastyz28.com/chevy-engine-code-stampings.php Suffix and VIN codes] from nastyz28.com

==Date code==
The date code is most often found back by where the transmission bolts to the engine block, on the top side of the block.

The date code generally has a letter followed by two or three numbers. The letter is the month. The next number or two numbers will be the day of the month. The last number is the last digit of the year. 
:Example: '''C124''' 
:*C = March (A = Jan., B = Feb., etc.)
:*12 = day of the month
:*4 = year ending in 4, i.e. 1964, 1974, 1984, etc.

==Factory hydraulic roller SBC block ID==
Hydraulic roller valve trains were used beginning in 1986. During this period, there were both roller and flat tappet (non roller) equipped engines available.
 
Some blocks came completely machined for a mechanical fuel pump. Others have either partial or no machining of the block to use a mechanical F/P.

It has been said that most or all of the c/n 638 blocks are ready to use a mechanical pump. In EFI applications, these engines will have a block off plate covering the mechanical pump area. Casting number 880 blocks have been seen both with and without mechanical pump provisions, and casting number 148 is mostly without the mechanical pump provision. 

Blocks with a 4" nominal bore diameter (as used on the 350/5.7L SBC engines) that are equipped to use the factory hydraulic roller valve train, are casting numbers: 
*10243880 (common casting number of a 5.7L Vortec engine)
*14011148
*14088526
*14093638

Some of the 1986-up Chevy small block engines used flat tappet (i.e. non-roller) cams. 350 cid/5.7L flat tappet blocks are casting numbers:
*10054727
*14079287
*14088548
*14101148
These flat tappet blocks '''''may''''' have the provisions for a roller cam (i.e. bosses present and drilled/tapped for the spider and for the cam plate, etc.), but also may '''not''' be equipped with the drilled and threaded bosses needed to use a factory roller valve train. In any event, these blocks originally had a flat tappet cam and non-roller lifters, no spider, and no cam thrust plate. These blocks are fine if you don't care about the roller cam. 

'''Note:''' There is a flat tappet block and a roller block that both end with the numbers 148. 14101148 is a flat tappet truck block, 14011148 is a roller provisioned block. 

==SBC Head casting numbers==
*[http://outintheshop.com/faq/casting/castings2.html SBC head casting number "go-to" site] from outintheshop.com
*[http://chevytech.info/3c10o12.html Head info by c/n, some with photos] from chevytech

==Dampers/balancers==
===SBC===
The earliest SBC 265 dampers had a riveted on crank pulley (red arrow) attached to a steel hub, as shown below.
{|
|[[File:Sbc 265 damper.jpg|thumb|left|500px|SBC 265 damper hub with attached pulley, front]]
|[[File:Sbc 265 damper2.jpg|thumb|left|500px|SBC 265 damper hub, back]]
|}

On other SBC engines, including internally balanced stroker engines, the dampers are neutral balanced. The differences will be in the location of the TDC line, weight, thickness and diameter of the dampers.

On the 400 SBC and externally balanced stroker engines, an OEM damper will have a scalloped portion to the outer ring which is easily seen. Aftermarket dampers usually use a bolted on counterweight, which is also usually easily seen.

Not as easily seen is the gap or void in the SBC 400 main bulkhead webbing.
[[File:Sbc400balancer.jpg|thumb|300px|left|OEM 400 balancer. Note scalloped outer ring]] [[File:Sbc400main web.jpg|thumb|400px||right|Void in 400 main webbing]]
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==BBC==

===Damper/balancers===
The 396/402 and 427 ci BBC engines were internally balanced. The 454 BBC engine is externally balanced. The 454 can be ID'd by the balancer having the inner hub cast with an integral counterweight (see image below). A 454 will also have a different flexplate/flywheel, having an added counterweight that is missing from the other displacement BBC engines. Like the SBC aftermarket dampers, the counterweight of a 454 damper might be bolted to the hub.

[[File:Bbc 454 damper.jpg|thumb|left|500px|BBC 454 balancer with inner ring scalloped]] <br style="clear:both"/>

===BBC notched bores===
A BBC block may have bores notched to clear the intake valves. Not present on all BBC engines.
[[File:BBC 454 BLOCK NOTCHED BORES.jpg]] <br style="clear:both"/>

===BBC external cues for 2- or 4-bolt bottom end===
While not 100%, a Mark IV BBC engine can sometimes be ID'd for being a 2- or 4-bolt bottom end by looking above the filter mount:
[[File:Bbc 4-bolt vs 2-bolt fittings id.jpg|550px]] <br style="clear:both"/>

==396 block boring==
Some 396 blocks will take an overbore to 4.250". One way to tell if the block has sufficient metal to do this is by removing a center freeze plug from the side of the block, then see if a ~1/4" wooden dowel (a pencil will do) will fit in between the cylinder jackets. If it fits the walls are probably not thick enough to bore to 4.250".

{{Note1}}This is not meant to be a replacement for sonic testing the bore thickness. It is only to judge whether the block is a candidate for sonic testing.

===Tall deck BBC===
The 10.2" deck height tall deck (TD) BBC was made in two different sizes: 366 and 427 cid. These engines were made to stand up to heavy duty use like bus and dump truck, etc. right up to where a diesel would be used. The tall deck height was to facilitate the height of the four ring piston used in the TD BBC engines. The bottom ends were forged and the rods were heavy duty-and heavy in weight.

These engines can be made into good performing engines without going to too much trouble or expense. '''[http://www.hotrodders.com/forum/cheapo-bbc-505-tall-deck-grunt-motor-164014.html#post1160950 Here]''' is a thread showing a budget build up of a 427 tall deck BBC.
 
If the engine is assembled, the stock intake had two thermostats on it and the intake is also wider due to the taller decks. The distributor is different and may have a different oil pump drive arrangement. 

One of the easiest ways to tell a tall deck BBC block from a standard 9.8" deck height BBC block is to check the distance from the top water pump bolt hole to the block deck. A standard block (below left) will have very little space between the hole and deck; a tall deck block will have around 1/2" between the hole and deck (below right).

[[File:454 deck.JPG]][[File:Bbc tall deck.jpg]]

==BBC 502==
A production Chevy 502cid block can be a Gen V or VI. It will have "8.2" cast into the block, and will have 4-bolt mains with a one piece rear main seal. 

A 454 bore diameter will be about 4.25". A 502 will be about 4.5".

==Resources==
*[[Chevy engine casting numbers]]

==Mortec info==
===Mortec SBC block casting numbers===
*Return to '''[[Identifying Chevy engines #SBC engine casting numbers|SBC engine casting numbers]] ''' above.
*Return to [http://www.crankshaftcoalition.com/wiki/Swirl_port_SBC_heads#Resources '''Swirl port SBC heads/Resources''']

<pre>SBC BLOCK CASTING NUMBERS

CASTING NUMBER.....SIZE...YEAR...MAIN CAP BOLTS....NOTES

140029.....350...80-84...2
330817.....400...72-80...2
355909.....262.....75....2
355909.....305...76-79...2
360851.....262...75-76...2...Monza V8
361979.....305...77-79...2 or 4, some Canadian assembled heavy duty blocks have 4-bolt main caps
366245.....350...78-79...4...Bowtie
366286...................4...Bowtie, siamesed, straight nodular iron main caps, 
2-piece seal, 4.00”-4.150" bores, 2.45" main journals
366298...................4...Bowtie, Aluminum, billet main caps, 3.398" bore 
with sleeves, two piece rear main seal
366299...................4...Bowtie, Aluminum, nodular iron splayed caps, 
wet sump, 4.00" bore
389257.....302.....67....2
393288.....283...65-67...2
460703.....350.....78....4
460776.....305...78-79...2
460777.....305...78-79...2
460778.....305...78-79...2 or 4, some Canadian assembled heavy duty 
truck blocks have 4-bolt main caps
471511.....267...79-82...2
3556519....283...58-61...2
3703524....265.....55....2...No oil filter
3720991....265...56-57...2
3731548....265...57......2...No side motor mounts
3731548....283...57......2...No side motor mounts
3737739....283...58-64...2
3756519....283...58-62...2
3782870....327...62-67...2
3789817....283...62-64...2
3789817....327...62-67...2
3789935....283...61-64...2
3790721....283...62-64...2...Chevy II recessed oil filter boss
3790721....327...65-66...2...Chevy II recessed oil filter boss
3791362....327...62-67...2...Chevy II recessed oil filter boss
3792563....327.....65....2
3792582....283...64-65...2
3794226....283...58-63...2
3794460....327...62-64...2
3830944....327.....63....2
3834810....283...64-66...2
3834812....283...62-63...2
3837739....283...58-62...2
3849852....283...57-66...2
3849935....283...65-67...2
3858174....327...64-67...2
3858180....327...64-67...2
3858618....350...68-76...2
3862194....283...65-67...2...Chevy II recessed oil filter boss
3862812....283...62-64...2
3892657....302.....67....2...Z-28 Camaro
3892657....327.....67....2
3892657....350.....67....2...Camaro
3896944....283...66-67...2
3896948....283...66-67...2
3903352....327.....67....2
3914636....307.....68....2
3914638....307.....68....2
3914653....307...68-73...2
3914660....327.....68....2
3914678....302.....68....2...Z-28 Camaro
3914678....327.....68....2
3914678....350.....68....2
3931174....307.....68....2...Truck
3932371....307...69-73...2
3932373....307...68-73...2
3932386....302.....69....4...Z-28 Camaro
3932386....327.....69....2
3932386....350.....69....2 or 4
3932388....327.....69....2
3932388....350.....69....2 or 4
3933180....327...68-69...2
3951509....400...70-71...4
3951509....400...74-80...2
3951511....400...70-73...4...Some replacement blocks had 2-bolt main caps
3956618....302.....69....4...Z-28 Camaro
3956618....327...68-69...2
3956618....350.....69....2 or 4
3956632....307.....69....2
3959512....327...62-67...2...Was also used for some "CE" replacement blocks
3959532....283...64......2...Used for some "CE" replacement blocks
3959538....327...........2...Chevy II recessed oil filter boss, used for 
some Chevy II "CE" replacement blocks
3970010....302.....69....4...Z-28 Camaro
3970010....327.....69....2...Trucks and industrial
3970010....350...69-80...2 or 4
3970014....350...70-76...2 or 4
3970020....307...69-73...2
3970024....307...69-73...2
4715111....305.....80....2
6259425....350...69-76...2
10036033...350...........4...Goodwrench crate motor, 2-piece rear seal, 
"Hecho en Mexico"
10046164...305.....86....2
10049804.................4...Aluminum, Pontiac Super Duty version of 
Gen. 1 SBC, 4.00" bore, 350 mains, 2-piece rear seal, splayed caps, 
GTP race block
10051182.................2 or 4...Bowtie, 3.75"-4.30" bores, 1 or 2-piece rear seal
10051184.................4...Bowtie, 4.00"-4.155" bores, 1 or 2-piece rear seal
10054727...350...86-up...2 or 4...one piece rear seal, some "Made in Canada"
10066036...350...........2 or 4...Target Master/Goodwrench crate motor, 
2-piece rear seal, "Hecho en Mexico"
10066038...350.....92....4...Goodwrench crate motor, 2-piece rear seal, 
"Hecho en Mexico"
10090511...350.....90....2...LT5, ZR1 Vette, 375hp
10125327...350...92-up...2 or 4...Gen. 2 LT1, reverse flow cooling
10125327...350...96-up...2 or 4...Gen. 2 LT4, reverse flow cooling
10134398.................4...Bowtie, Aluminum, 4.125" bore, 2.65" main journals
10134996.................4...Bowtie, Aluminum, 4.125" bore, 2.65" main journals
10153558...350...91-92...4...LT5, ZR1 Vette, 375hp
10168588...265...94-96...2...L99, Gen. 2, 4.3 Liter V-8, Caprice, 
reverse flow cooling
10199001...350...93-95...4...LT5, ZR1 Vette, 405hp
10243878...305...96-98...2...Vortec truck, roller cam, one-piece rear seal
10243880...350...95-00...2 or 4...Vortec truck, Gen. 1 crate motors and "ZZ4", 
roller cam, one piece rear seal
12550592...350...97-up...crossbolted block, Gen. 3, "LS1", aluminum
12551358.........99-up...Gen. 3, 4.8L or 5.3L, cast iron, truck
12551364...364...98-04...crossbolted cast iron Gen. 3, 6.0L, truck
12559378...350...99-up...crossbolted block, Gen. 3, "LS1", aluminum
12559846...350...98-up...crossbolted block, Gen. 3, "LS1", aluminum
12560621...350...98-up...crossbolted block, Gen. 3, "LS1", aluminum
12560626...350...99-up...crossbolted block, Gen. 3, "LS1", aluminum
12560629...350...99......crossbolted block, Gen. 3, "LS1", aluminum
12561168...350...01-up...crossbolted block, Gen. 3, "LS1", aluminum
12562174...350...98-up...crossbolted block, Gen. 3, "LS1", aluminum
12568952...364...05-up...crossbolted block, Gen. 3, 6.0L, aluminum, LS2
12566910...325...04-up...crossbolted block, Gen. 3, 5.3L, aluminum, SSR truck
12571048...325...04-up...crossbolted block, Gen. 3, 5.3L
12573581...364...98-04...crossbolted cast iron, Gen. 3, 6.0L, truck
12577184...364...98-04...crossbolted cast iron, Gen. 3, 6.0L, truck
12577396.........02-up...Gen. 3, 4.8L or 5.3L, cast iron, truck
14010201...305...80-85...2
14010202...305...80-85...2
14010203...305...80-85...2
14010207...350...80-85...2 or 4
14010209...350...80-85...2 or 4
14010280...267...79-82...2
14011064...350...83......4
14011148...350...87-89.......Roller cam, one-piece rear seal
14016376...267...79-82...2
14016379...350...77-79...2 or 4
14016381...305...80-84...2
14016382...305...79-84...2
14016383...305...80-85...2...Truck
14079287...350...86-90.......Truck
14088526...350...87-89.......Roller cam, one-piece rear seal
14088548...350...86-88...2 or 4
14088551...305...86-87...2...one-piece rear main seal
14093627...305...87-94...2...Roller or flat tappet cam, one-piece rear seal
14093638...350...87-95...2 or 4...Roller or flat tappet cam, one-piece rear seal
14094766...305...86-up...2...One-piece rear seal
14101147...305...85-up...2
14101148...350...86-90...4...One-piece rear seal
14102058...305...87-91...2...Roller cam, one-piece rear seal
22551656.................4...Chevy/Olds Rocket block, 4.00"-4.190" bores, 
2.45" main journal, splayed caps, dry sump, 2-piece rear seal, 9.025" deck
22551660.................4...Chevy/Olds Rocket block, 4.00"-4.190" bores, 
400 main journal, splayed steel caps, wet sump, raised cam, 
2-piece rear seal, 9.300" deck
</pre>

===Mortec SBC head casting numbers===
<pre>SMALL BLOCK HEAD CASTING NUMBERS:

330545.....73......350..........76cc chamber, 2.02”/1.60”
333881.....74-75...350..........76cc chamber, 2.02”/1.60”
333882.....74-80...350/400......76cc chamber
340292.....70's.......Over the counter, angle plug, 64cc chamber
354434.....75-79...262/267/305...60cc chamber
358741.....76-79...305
376445.....77-85...350..........76cc chamber, small valves
376450.....75-81...262/267/305..6 or 7 exhaust bolt holes, 60cc chamber
462614.....77-79...305..........60cc chamber
462624.....75-86...350/400......76cc chamber, 1.72”/1.5”, 1.94”/1.5” or 
2.02”/1.6” valves
458642.....75-84...350..........350
468642.....76-up...350/400
471513.....79......267/350
517513.....79......267/350
1816887....63......283..........Made in Canada, GMC HD truck
3636839....55......265
3703523....55......265
3713358....55-56...265
3713569....55-56...265
3725306....56......265
3731539....57......283..........283 HP FI
3731544....57-61...283
3731554....57-62...283
3731556....57......283..........Truck, made in Canada
3731762....56......265..........Vette, 2x4 carbs
3737775....62-67...283/327
3740997....57......283..........1x4, 2x4 & FI (exc. 283hp)
3743056....58......283
3743096....62-67...327..........GMC Truck
3747363....57-61...283
3747460....59-67...283/327......70cc chamber
3748770....58......283
3748772....58-61...283
3755537....57-62...283
3755539....58-62...283
3755549....57-62...283
3755550....59......283
3755585....62-67...327..........GMC Truck
3767460....59-60...283
3767462....62-67...327
3767465....59-61...283
3767754....59-61...283..........60cc chamber
3767792....60-64...283
3774682....60-64...283/327......70cc chamber
3774684....62-64...327..........75cc chamber
3774692....58-64...283..........60cc chamber
3782461....64-66...327......Camel hump, no accessory holes, 
160cc/62cc port volumes, 62cc chamber
3782461X...60-63...283/327..Camel hump, no accessory holes, 
larger 172cc/64cc port volumes, 62cc chamber
3795896....63-65...283......60cc chamber
3795896....62-64...327......60cc chamber
3798996....63-67...327
3814480....60-67...283/327..70cc chamber, 1.72”/1.5” valves
3814482....62-67...283/327/350..75cc chamber
3817680....63-67...283/327
3817681....62-67...327
3817682....61-62...283
3836839....55......265
3836842....57-67...283/327
3837064....56-62...265/283
3837065....55-56...265..........Truck
3848720....57-58...283
3876775....60-67...283/327......75cc chamber
3884520....60-67...283..........Some marked "Made in Canada", 
60cc chamber, also used by Studebaker
3884520....62-67...327..........Some marked "Made in Canada", 
60cc chamber, also used by Studebaker
3890462....66-67...302/327/350..Camel hump, no accessory holes, 
64cc chamber
3901068....87-up...350..........Crate motor, 285hp, 64cc chamber
3911032....68......307/327......70cc chamber
3912264....58-62...283
3912265....63-64...283
3912311....65-67...327
3912313....65-67...327
3917290....67-68...307/327
3917291....67-68...302/327/350..Camel hump, no accessory holes, 
64cc chamber
3917292....68......327/350......Camel hump, 64cc chamber
3917293....67-68...307/327......75cc chamber 
3927185....69-76...307/327/350..70cc chamber 
3927186....69-70...302/350......Camel hump, 64cc chamber, accessory holes
3927187....69-70...350..........Camel hump, 64cc chamber, accessory holes
3927188....69......327..........74cc chamber
3927188....70......307..........74cc chamber
3931633....68-73...307
3931635....68-76...350
3931638....68......327..........Truck
3932441....69-70...350..........76cc chamber
3932441X...69-70...350/400......80cc chamber
3932454....69-73...307
3932454....69-79...350..........Truck
3946812....69......350
3946813....69-79...350..........Truck
3947040....68......327.........."Right angle" casting identifier, 
64cc chamber, good HP head, used in trucks, no accessory holes
3947041....69-70...302/350......"Right angle" casting identifier, 
64cc chamber, accessory holes, good HP head
3947041X...69-70...302/350......"Right angle" casting identifier, 
64cc chamber, 165cc intake port, accessory holes, good HP head
3951598....70......400..........76cc chamber
3964286............350
3965742....70......350..........Over the counter, angle plug
3970126....67-71...327/350
3973370....69-70...350..........Over the counter in US, 
Canadian 350/300hp production use in Pontiac, 64cc, straight or angle plug
3973414....70......350..........LT1-350/370hp, camel hump, 64cc chamber
3973487....71-72...350..........1.94”/1.5” or 2.02”/1.6” valves, 
was also used on '71 350/330hp LT1, 75cc chamber
3973487X...71-72...350..........1.94”/1.5” or 2.02”/1.6” valves, 75cc chamber
3973493....71-72...400..........76cc chamber
3986316....71......350..........76cc chamber
3986336....71......350..........76cc chamber
3986336X...71......350..........76cc chamber
3986339....71......307/350......74cc chamber
3986339X...71......307/350......74cc chamber
3986388....68-76...307/350
3991492....70......350..........LT1, camel hump, accessory holes, 
64cc, straight plug
3991492....70-up................Over the counter, camel hump, 64cc, 
straight or angle plug
3998916....72......350..........Also used w/'72 350 LT1, big valves, 
screw in studs, 76cc chamber
3998920....72-73...350
3998991....72-73...307/350......75cc chamber
3998993....72-73...307/350......75cc chamber
3998993....current..350.........Goodwrench crate motors, "Hecho en Mexico", 
75cc chamber
3998997....72-73...350/400......76cc chamber
3998997....78-84...305/350......76cc chamber
4079261....75......350
10033867........................Aluminum , over the counter Pontiac 23º 
head, 62cc, angle plug, 196cc intake port
10045434........................Over the counter Pontiac 15º  head, 
55cc, angle plug, raised runner, aluminum, "roll over" head
10051101........................Bowtie, aluminum, 55cc, angle plug, 
raised runner, 196cc intake port
10065202...87-95...350..........Truck
10065203...87-95...350..........Truck
10065204...87-95...350
10065205...87-95...305
10065206...87-95...350 
10065207...87-95...305
10088113...88-up...350..........Aluminum, 58cc, angle plug, raised "D"-port 
exhaust, 1.94"/1.5" valves
10093328........................Over the counter, Pontiac 15º head, 
aluminum, 224cc intake port, 61cc chamber, "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...91-up...350..........Gen. 1, 65cc chamber
10120928...87-95...350
10125320...94-96...350..........Gen. 2 LT1, cast iron version, 
used on "9C1" Police package, Impala SS,
Cadillac Fleetwood, Buick Roadmaster, reverse flow cooling 
10128374...92-up...350..........Gen. 2 LT1, 53cc, angle plug, 
aluminum, reverse flow cooling, 175cc/68cc ports
10134352........................Bowtie, 45cc, angle plug, "low" port, 
223cc intake port, aluminum, 18º race head
10134363........................NOTE: This casting # has been used in 
several different versions of aluminum 18º and 15º Bowtie race heads. 
Different chamber volumes, port volumes, port locations, valve sizes, 
etc. were used. Check this casting carefully to determine which features 
it may have. There are at least six different versions as of 11/99.
10147898...95-98...350..........Gen. 1 crate motor
10159550...87-95...350
10159551...87-95...305
10159552...87-95...350
10159553...87-95...305
10174389...91-94...350..........LT5, ZR1, DOHC, 32-valve, drvs. side, aluminum
10174390...91-95...350..........LT5, ZR1, DOHC, 32-valve, pass. side, aluminum
10185040........................Bowtie, aluminum, 45cc chambers, 1st. version, 
symmetrical ports, 263cc intake port, splayed valves
10185040........................Bowtie, aluminum, 45cc chamber, 2nd. version, 
symmetrical ports, 240cc intake port, splayed valves
10205245...93......350..........Gen. 2 LT1, aluminum, reverse flow cooling, 
175cc/68cc port volumes
10207643...94-96...350..........Gen. 2 LT1, aluminum, reverse flow cooling, 
175cc/68cc port volumes
10208890...94-96...265..........Gen. 2, L99, 4.3 Liter V8, cast iron, reverse flow
10215339...97......350..........Gen. 3, LS1, aluminum, 68cc
10225121...94-95...350..........LT5, ZR1, DOHC, 32-valve, drvs. side, aluminum
10225122...95......350..........LT5, ZR1, DOHC, 32-valve, pass. side, aluminum
10239902...96-up...350..........Gen. 2 LT4, aluminum, reverse flow cooling, 
195cc port, 54.4cc chamber, angle plug
10239906...96-up...350.........."Vortec 5700", "L31", 64cc chamber, 
170cc intake port, 1.94"/1.5" valves
12367712...99-up................"Fast Burn", aluminum, 210cc intake port, 
2.00”/1.55” valves, 62cc chamber
12367713...99-up................"Fast Burn" used on ZZ430 crate motor, 
aluminum, 210cc intake port, 2.00”/1.55” valves, 62cc chamber
12480005...2000.................LS1 "GTZ", aluminum, 38cc chamber, 
2.125"/1.625" valves, angle plug
12480011...97-up................Bowtie "SB2.2", aluminum, 2nd. version of "SB2", 
48cc chamber, "mirror ports", revised valve angles & plug location
12506450...87-95...350
12509859...87-94...305
12516852...87-95...350
12529742...95-96...265..........Gen. 2, "L99", cast iron
12551561...96......350..........Gen. 2, "LT1", aluminum
12552520...97-up...305..........Vortec, truck
12554290...94-96...350..........Gen. 2, "LT1", cast iron version, 
used on "9C1" police package, Impala SS,
Cadillac Fleetwood, Buick Roadmaster, reverse flow cooling
12554291...95-96...265..........Gen. 2, "L99", cast iron
12555690...96......350..........Gen. 2, "LT4", aluminum
12556743...99......325..........Gen. 3, 5.3L, aluminum, truck, van
12558059...97......305..........Vortec, truck, 1.84"/1.5" valves
12558062...98......350..........L31 Vortec, truck, 64cc chamber, 
1.94”/1.5”, 170cc intake port
12558806...97-98...350..........Gen. 3, "LS1", aluminum, 68cc chamber
12559853...99-up...350..........Gen. 3, "LS1", aluminum, 68cc chamber
12559862...99-00................Gen. 3, aluminum 4.8/5.3L
12559895...00-up...325..........Gen. 3, aluminum, Vortec 5.3L
12561706...01-04................Gen. 3, 5.3L, aluminum
12561873...99-01...364..........Gen. 3, 71cc, iron
12562317...01-04...364..........Gen. 3, 71cc, aluminum
12564241...00-up...350..........Gen. 3, "LS1", aluminum, 68cc chamber
12564243...01-up...350/364......Gen. 3, "LS6", "LS2", aluminum
12572035...01-04...364..........Gen. 3, 6.0L, aluminum, 71cc chamber
14008856...79-81...267
14010201...82-85...305
14011034........................Bowtie, cast iron, 64cc chamber, 
184cc intake port volume, angle plug, "Phase 2" head
14011049........................Bowtie, aluminum, 55cc chamber, 
angle plug, 180cc intake port volume, "Phase 6"
14011083...55-86...350..........Crate motor for years indicated.
285/300hp, 64cc chamber, 1.94"/1.5" valves
14014415...80-85...267/305
14014416...80-86...305..........1.84"/1.5" valves, 58cc chamber
14014440...80......305..........1.84"/1.5" valves
14019821...80-86...350
14019924...79-81...267
14019926...80-86...350
14010516...80-86...350
14020517...80......350
14020555...81......305
14020556...81......350
14022056...85......350
14022206...80......350
14022301...80-86...305
14022601...80-86...267/305......1.72"/1.5" or 1.84"/1.5" valves, 53cc chamber
14022801...80-86...305
14024816...........350..........76cc chamber, 1.94”/1.5” valves, 
Gen. 1 crate motor
14034806...78-82...267
14034807...78-86...305
14034808...80-86...350
14034808...96-up...350..........76cc chamber, 1.94"/1.5" valves, 
Gen. 1 Goodwrench crate motor
14034810...80-86...350..........Truck
14034811...80-86...350..........Truck
14039121...81-86...305..........Truck
14039122...81-86...305..........Truck
14071114...80-86...350
14075381...80-86...350..........Truck
14079261...86......350
14085844...80-86...350..........Truck
14085963...86......350
14088526...........350..........Gen. 2, LT1, aluminum
14089119...86-88...350
14094093...86-88...350
14096217...55-86...350..........Crate motor, 285hp/300hp, 64cc chamber, 
72º or 90º center intake manifold bolt angles
14101081...87-95...305
14101083...87-up...350..........Gen. 1, also used on crate motors, 
285 or 300 hp, 64cc chamber, 72º center manifold bolt angles
14101128...86-87...350..........Aluminum, 58cc, angle plug
14102187...87-91...305..........1.84"/1.5" valves
14102191...87-up...350
14102193...87-up...305/350......1.94"/1.5" valves
22542525........................Dart/Olds/Chevy aluminum, 
14º or 17º race head
24502559...96-97................Bowtie, "SB2", 1st. version, 
"mirror ports", aluminum, 196cc port, CNC version 280cc port, 38cc chamber
25500141........................Buick/Chevy aluminum, 10º race head, 
42cc chamber, symmetrical ports, 235cc intake port volume, 2.1"/1.625" valves
25534351C..04-up................Gen. 1 Bowtie, cast iron Vortec head, 
175cc/65cc ports, 2.00”/1.55” valves, "small port” head
25534371C..04-up................Gen. 1 Bowtie, cast iron Vortec head, 
206cc/77cc ports, 2.00”/1.55” valves, "large port” head
33417369...90-up...350..........Gen. 1 Goodwrench crate motor, 
"Hecho en Mexico", 76cc chamber
</pre>

===Mortec BBC block casting numbers===
<pre>BIG BLOCK CHEVY BLOCK CASTING NUMBERS:
NOTE: T = tall deck
Oval includes both "peanut" (also called "round") ports and large oval ports

0-326711.....................4-bolt, alum., CanAm, 4.44" bores, 
steel cylinder liners
340220.....427T......68-85...4-bolt
345014.....454.......70-86...
346236.....454.......75-76...2-bolt
359070.....454.......70-90...
361959.....454.......73-90...2 or 4 bolt
364776.....427T......68-85...4-bolt
364779.....366T......68-90...4-bolt
399204.....509.......70-71...4-bolt, alum., CanAm, 4.5" bores, 
steel cylinder liners
399293.....366T......77-78...4-bolt
473478.....427T......77-90...4-bolt
495102.......................4-bolt, alum., CanAm, 4.5" bores
3782870....427T......68-76...4-bolt
3824553....366T......66-67...4-bolt
3855961....396.......65-66...2 or 4 bolt
3855961....427.......66......2-bolt
3855962....396.......65-66...4-bolt
3855977....366T......66-73...4-bolt
3869942....427.......66-67...2 or 4 bolt
3902406....396.......67......2 or 4 bolt
3904351....427.......67......2 or 4 bolt
3904354....366T......66-76...4-bolt
3916319....366T......68......4-bolt
3916321....427.......68......2 or 4 bolt
3916323....396.......68......2 or 4 bolt
3925521....427T......68-85...4-bolt
3935439....427.......68-69...2 or 4 bolt
3935440....396.......68-69...2 or 4 bolt
3937724....366T......68-85...4-bolt
3937726....427T......68-84...4-bolt
3946052....427.......69......4-bolt, alum. ZL-1, Mark IV
3946053....427.......97-up...4-bolt, alum. ZL1, 2nd. version, Mark IV
3955270....427.......69......2 or 4 bolt
3955272....396.......69......2 or 4 bolt
3955274....366T......68-85...4-bolt
3955276....427T......68-73...4-bolt
3963512....427.......69......2 or 4-bolt
3963512....454.......70-76...2 or 4-bolt
3969852....366T......68-84...4-bolt
3969854....396.......69......2 or 4-bolt
3969854....402.......70-72...2 or 4-bolt
3969858....427T......68-84...4-bolt
3999289....454.......71-79...2 or 4-bolt, some "CE" replacement blocks 
had four bolt main caps
3999290....396.......68-69...2 or 4-bolt, truck
3999290....402.......70-72...2 or 4-bolt, truck
3999290....402.......72......2 or 4 bolt, passenger car
3999293....366T......68-90...4-bolt
3999294....427T......68-84...4-bolt
10051107...454...............4-bolt, Bowtie, Mark IV, 9.8" deck, 
siamesed bores, 4.25" semi-finished bores, can be bored to 4.50"
10069282...366T......90-91...4-bolt, Mark IV, tall deck
10069284...427T..............4-bolt, Mark IV, tall deck
10069286...454.......90-91...4-bolt, Mark IV, short deck
10114182...454.......91-up...4-bolt, Gen. 5
10114183...366T......91-up...4-bolt, Gen. 5
10114184...427T......91-up...4-bolt, Gen.5
10134366...454T..............4-bolt, Bowtie, Gen. 5, tall deck
10185050...454...............4-bolt, Bowtie, Gen. 5, short deck
10237297...454.......96-up...4-bolt, Vortec 7400", "L-29" Gen. 6
10237299...427T......96-up...4-bolt, Gen. 6, 7.0L, truck
10237300...502.......96-up...4-bolt, Gen. 6, 4.466" bore
12550312...427T......96-up...4-bolt, Gen. 6, 4.250" bore, fuel pump boss, 
clutch linkage pivot boss
12550313...454.......91-up...4-bolt, Gen. 5 crate motor, Gen. VI 4.25" 
bare block, fuel pump boss
12556110...496.......01-up...4-bolt, Gen. 7, 8.1L, "Vortec 8100", truck
12561357...454.......96-up...4-bolt, Gen. 6
12561358...502...............4-bolt, Gen. 6
14015443...454.......87-90...2 or 4-bolt, Mark IV, truck, motorhome
14015445...454.......78-90...2 or 4-bolt
14044807...454T..............4-bolt, Bowtie, Mark IV, CNC prep, tall deck, 
4.25" or 4.495" bores
14096859...502...............4-bolt, Gen. 5, HO
24502504...454...............4-bolt, Bowtie, Gen. 5, race prep, 
9.8” "short" deck height
24502506...454T..............4-bolt, Bowtie, Gen. 5, race prep, 
10.2” "tall" deck height
24502572.....................4-bolt, 4.5" bore Olds DRCE 2, 9.5" deck height
25534402.....................4-bolt, 4.590" bore Olds DRCE 3, 9.25" deck height
</pre>

===Mortec BBC head casting numbers===
<pre>BIG BLOCK CHEVY HEAD CASTING NUMBERS:

330864.....68-84...oval...OPEN...396, 402, 366T, 427T, 454 Truck
330865.....68-84...oval...OPEN...396, 402, 366T, 427T, 454 Truck
330866.....68-78...oval...OPEN...366T, 427T
330867.....68-73...oval...OPEN...427T
336765.....68-78...oval...OPEN...427T
336768.....73-76...oval...OPEN...427T
336781.....73-85...oval...OPEN...454, 118cc chamber, 256cc/114cc ports
343771.....68-86...oval...OPEN...366T, 427T, 454
343772.....68-86...oval...OPEN...366T, 427T, 454
343783.....70-76...oval...OPEN...454 truck
346236.....75-87...oval...OPEN...454, 120cc chamber, 225cc/116cc ports
352625.....70-76...oval...OPEN...454 truck
353049.....73-84...oval...OPEN...454, 122cc chamber, 255cc/119cc ports
366765.....74-78...oval...OPEN...427T
473328.....68-69...oval...OPEN...366T
3856206....65-66...oval..CLOSED..396, 97cc chamber
3856208....65......rect..CLOSED..396/425hp, 109cc chamber
396/375hp "Z-16" Chevelle
3856213....66-82...oval..CLOSED..366T, 427T
3856260....68......oval..CLOSED..396 truck
3872702....65-66...oval..CLOSED..396, 427, 98cc chamber
3873858....65-67...rect..CLOSED..396, 427, 109cc chamber
3876875....77-85...oval...OPEN...427T
3904390....67......oval..CLOSED..396, 427, 98cc chamber
3904391....67......rect..CLOSED..396, 427, 107cc chamber
3904392....67......rect..CLOSED..427, aluminum, L88, L89, 107cc chamber
3904393....68-76...oval...OPEN...366T
3908952....67......oval...OPEN...427, truck, marine
3909802....67......oval..CLOSED..396, 427, 101cc chamber
3917215....67-68...oval..CLOSED..396, 427, 101cc chamber
3917219....68-85...oval...OPEN...366T, 427T
3919840....67-69...rect..CLOSED..396, 427, 107cc chamber
3919842....68-69...rect..CLOSED..396, 427, aluminum L88, L89, 107cc chamber
3931063....68-69...oval..CLOSED..396, 402, 427, 101cc chamber
3933148....69-84...oval...OPEN...'69 396/265hp, 366T, 427T, 112cc chamber
3933149....68-76...oval...OPEN...427T, 122cc chamber
3935401....68-76...oval...OPEN...427T
3946074....69&71...rect...OPEN...'69 427 L88, ZL1, aluminum, 118cc chamber, 
'71 454 LS6, "round exhaust port"
3964290....69-70...oval..CLOSED..396, 402, 427, 454, 101cc chamber, 
large or small hex spark plugs used
3964291....69-72...rect..CLOSED..396, 402, 427, 454, 109cc chamber, 
large or small hex spark plugs used, crate motor usage in years after 1970
3965198....68-69...oval..CLOSED..396 truck
3975950....68-70...oval...OPEN...396, 402 Truck, 366T, 427T
3986133....68-85...oval...OPEN...366T, 427T, 454 truck
3986135....69-73...oval...OPEN...366T, 427T
3986136....68-84...oval...OPEN...366T, 427T, 454 truck
3993820....71......oval...OPEN...402, 113cc chamber, 255cc/114cc ports
3993820....71-84...oval...OPEN...454 passenger and trucks, 113cc chamber, 
255cc/114cc ports
3994026....71......rect...OPEN...454 LS6, 118cc chamber
3999241....72......oval...OPEN...402, 454, 113cc chamber
6272292....70-78...oval...OPEN...402, 454
6272990....70-up...rect...OPEN...454 service replacement, used on some 
Mark IV crate engines, 118cc chamber
10045427...........rect..........Pontiac/Chevy, aluminum, 91cc chamber, 
large port, race
10049875...........rect..........Pontiac/Chevy, aluminum
Small port, race
10051128...........rect..........Bowtie, aluminum, 72cc chamber, 
symmetrical ports
10051129...........rect..........Bowtie, aluminum "raw" casting, 
symmetrical ports
10052902...........oval...OPEN...Mark IV, 427T
10101140...91-up...oval..CLOSED..Gen. 5 366T, 427T
10114156...91-up...oval...OPEN...Gen. 5 & 6 454, 118cc chamber
10141279...96-up...oval..CLOSED.."Vortec 7400", 100cc chambers
10487052...77-90...oval...OPEN...366T
12363391...96-up...oval...OPEN...Bowtie, aluminum, Signature Series, 
fits Mark IV, Gen. 5, Gen. 6, 110cc chamber
12363401...96-up...rect...OPEN...Bowtie, aluminum, Signature Series, 
fits Mark IV, Gen. 5, Gen. 6, 118cc chamber
12558162...01-up...oval..CLOSED..Gen. 7, "Vortec 8100", 8.1L, 496, truck
12560241...98-up...oval..CLOSED.."Vortec 7400", 100cc chamber 
12562932...91-95...oval...OPEN...Gen. 5, truck crate motor, 118cc chamber 
12562933...91-95...oval...OPEN...Gen. 5, 118cc chamber 
12562934...00-up...rect...OPEN...Gen. 6, 502 marine
14011077...69-up...rect...OPEN...aluminum, fits Mark IV, "C-port", 
118cc chamber, also sold as a "solid" head
14044861...84-96...rect..........Bowtie, aluminum, Mark IV, "raised runner", 
1st. design, 105cc chamber
14044861...96-up...rect..........Bowtie, Aluminum, Signature Series, 
fits Mark IV, Gen. 5, Gen. 6, "raised runner", 2nd. design, 115cc chamber
14044861...84-96...rect..........Bowtie, aluminum, Mark IV, "raw" casting 
of "861" Mark IV 1st. design
14081045...78-87...oval...OPEN...454
14081052...85-87...oval...OPEN...366T, 427T, 454 Truck, marked "HiPerf"
14092359...86-90...oval...OPEN...366T, 427T, marked "HiPerf"
14092360...86-90...oval...OPEN...454 truck, "peanut" round ports
14096188...70-71...rect...OPEN...454 service replacement, also used on 
later Mark IV LS-6, LS-7 and 454 HO crate motors, 116cc chamber
14097088...91-up...rect...OPEN...Gen. 5, 454/502 HO, 118cc chamber
24502585...97......rect..........Olds/Chevy, DRCE 2, Pro Stock aluminum, 
for blocks w/4.900" bore spacing
25534404...04......rect..........Olds/Chevy, DRCE 3, Pro Stock, aluminum, 
for blocks with 4.900" bore spacing
</pre>

===Other Mortec info===
<pre>CHEVY SMALL BLOCK CRANKSHAFT CASTING NUMBERS: 

WITH 2-PIECE REAR MAIN OIL SEAL

1130.......327.......forged..medium journal...3.25" stroke
1178.......302.......forged..medium journal...3.00" stroke
1181.......305,350...cast....medium journal...3.48" stroke
1182.......350.......forged..medium journal...3.48" stroke
2680.......327.......forged..small journal....3.25" stroke
2690.......350.......forged..medium journal...3.48" stroke
3279.......302.......forged..medium journal...3.00" stroke
3474.......283.......forged..small journal....3.00" stroke, military tank use
4577.......327.......forged..small journal....3.25" stroke
4672.......327.......forged..medium journal...3.25" stroke
310514.....350.......cast....medium journal...3.48" stroke
330550.....350.......cast....medium journal...3.48" stroke
354431.....262.......cast....medium journal...3.10" stroke
3727449....283.......forged..small journal....3.00" stroke
3729449....265.......forged..small journal....3.00" stroke
3734627....327.......forged..small journal....3.25" stroke
3735236....265,283...forged..small journal....3.00" stroke
3735263....283.......forged..small journal....3.00" stroke
3782680....327.......forged..small journal....3.25" stroke
3814671....327.......forged..small journal....3.25" stroke
3815822..265,283,302.forged..small journal....3.00" stroke
3835236....283.......forged..small journal....3.00" stroke
3836266....283.......forged..small journal....3.00" stroke
3848847....283.forged or cast..sm. journal....3.00" stroke
3849847....283.......forged..small journal....3.00" stroke
3876764....283.forged or cast..sm. journal....3.00" stroke
3876768....283.......forged..small journal....3.00" stroke
3884577....327.......forged..small journal....3.25" stroke
3892690....350.......forged..medium journal...3.48" stroke
3911001....307,327...cast....medium journal...3.25" stroke
3911011....307,327...cast....medium journal...3.25" stroke
3914672....327.......forged..medium journal...3.25" stroke
3923279....302.......forged..medium journal...3.00" stroke
3932442..267,305,350..cast...medium journal...3.48" stroke
3941174....307,327...cast....medium journal...3.25" stroke
3941178....302.......forged..medium journal...3.00" stroke
3941182....350.......forged..medium journal...3.48" stroke
3941188....350.......forged..medium journal...3.48" stroke
3949847....283..forged or cast..small journal...3.00" stroke
3951130....327.......forged..medium journal...3.25" stroke
3951529....400.......cast....large journal....3.75" stroke

WITH 1-PIECE REAR MAIN OIL SEAL

10168568...265.......cast....medium journal...3.00" stroke
12552215...364.......cast....medium journal...3.62" stroke, Gen. 3, 6.0L
12552216...325,350,364.......cast....medium journal...3.62" stroke, 
Gen. 3 5.7L LS1, 5.3L, 6.0L
12553312...293.......cast....medium journal, 3.27" stroke, Gen. 3, 4.8L
12553482...293.......cast....medium journal, 3.27" stroke, Gen. 3, 4.8L
14088526...305,350...cast....medium journal...3.48" stroke
14088532...350.......forged..medium journal...3.48" stroke
14088535...305,350...cast....medium journal...3.48" stroke
14088552...350.......forged..medium journal...3.48" stroke


ZR1, "LT5", 350 DOHC

10106122...350.......forged..large 2.76" journal...3.66" stroke


CHEVY BIG BLOCK CRANKSHAFT CASTING NUMBERS:

3.76" STROKE WITH 2-PIECE REAR MAIN OIL SEAL 
Used on '65-'90 Mark IV 366T, 396, 402, 427 and 427T

6223.......396,402,427...forged, 1053 steel
7115.......396,402,427...forged, nitrided, cross-drilled, 5140 steel
3804816....396,402,427...cast
3856223....396...forged
3863114....402...
3863144....396,402...
3874874....396,402...
3879621....427...forged
3882841....396...forged, cross drilled, nitrided
3882842....427...forged, cross drilled, nitrided
3882847....
3882848....
3882849....427...forged
3887114....396...forged, nitrided, 5140 steel
3904815....396,402...cast, nodular iron
3941180....
3942411....
3965746..........semi- finished, forged
3993804..........raw, 5140 steel

3.76" STROKE WITH 1-PIECE REAR MAIN OIL SEAL 
Used on '91-up Gen. 5 and Gen. 6, 366T, 427T

10114186...427T...forged, 1053 steel
10114187...366T...cast
10114189...427T...cast


4.00" STROKE WITH 2-PIECE REAR MAIN OIL SEAL 
Used on '70-90 Mark IV 454 or Mark IV 502

3520.......454...forged, cross-drilled, 1053 steel
3521.......454, 502...forged, cross-drilled, 5140 steel
3524.......454...forged
7416.......454, 502...forged, cross-drilled, 1053 steel
7463.......454...forged
336782.....454...cast
353039.....454...cast
353638.....454...
359730.....454...
3962523....454...forged
3963523....454...
3963524....454...forged
3967416....454...forged
3967463....454...forged
3975945....454
3963521....454...forged, cross drilled, 5140 steel
3965753..........semi-finished, forged, 5140 steel
3975495....454
3993878....454...forged
10051169...454...forged raw casting

4.00" STROKE WITH 1-PIECE REAR MAIN OIL SEAL 
Used on '91-up Gen. 5 and Gen. 6 454 or 502

10114188...454......cast
14097044...454, 502..forged, 1053 steel


348/409/427 W-ENGINE BLOCK CASTING NUMBERS:

3732755.....348......59-61
3732811.....348......58
3751872.....348......58
3755011.....348......59-61
3771705.....348......59-61
3782012.....348......58-61
3788068.....409......62-63
3795623.....409......61
3798962.....348......62-65...truck
3815707.....348......58-61
3830814.....427......63......"Z11" (4.312" bore x 3.65" stroke)
3830814.....409......63-64
3839752.....409......62-63
3839754.....409......65
3844422.....409......63-65
3857655.....348......62-65...truck
3857656.....409......64-65
3860386.....409......62-64
3860387.....348......58 


348/409/427 W-ENGINE HEAD CASTING NUMBERS:

3732791.....348......58-60
3758379.....348......59-61...250 hp
3759256.....348......58
3759332.....348......58-60
3764702.....348......60......truck
3767738.....348......59-60...250 hp
3781147.....348......60-61...HiPerf, 2.06"/1.72" valves
3781173.....348......60......1.94"/1.66" valves
3795586.....348/409..61......HiPerf, 2.06"/1.72" valves
3814690.....409......62-63...HiPerf, 2.19"/1.72" valves
3815643.....348/409..58-62...truck, industrial
3815857.....348/409..58-62...truck
3819333.....348/409..62-65...HD Truck
3830817.....409......63-65...340 hp
3837731.....427......63......"Z11" (4.312" bore x 3.65" stroke)
3852583.....409......63-65...HiPerf, 2.19"/1.72" valves

CHEVY 348/409/427 W-ENGINE CRANKSHAFT CASTING NUMBERS:

3732692...348...forged...3.25" stroke
3733223...348...forged...3.25" stroke
3733226...348...forged...3.25" stroke
3741640...348...forged...3.25" stroke
3741642...348...forged...3.25" stroke
3788072...409...forged...3.50" stroke
3795589...409...forged...3.50" stroke
3824553...348...forged...3.25" stroke
3829027...409...forged...3.50" stroke
3837466...409,427 "Z11"...forged...3.65" stroke
3838416...409...forged...3.50" stroke


CHEVY SMALL BLOCK BORE AND STROKE

262 = 3.671" x 3.10" (Gen. 1, 5.7" rod)
265 = 3.750" x 3.00" ('55-'57 Gen. 1, 5.7" rod)
265 = 3.750" x 3.00" ('94-'96 Gen. 2, 4.3 liter V8 "L99", 5.94" rod)
267 = 3.500" x 3.48" (Gen. 1, 5.7" rod)
283 = 3.875" x 3.00" (Gen. 1, 5.7" rod)
293 = 3.779" x 3.27" ('99-later, Gen. 3, "LR4" 4.8L Vortec, 6.278" rod)
302 = 4.000" x 3.00" (Gen. 1, 5.7" rod)
305 = 3.736" x 3.48" (Gen. 1, 5.7" rod)
307 = 3.875" x 3.25" (Gen. 1, 5.7" rod)
325 = 3.779" x 3.622" ('99-later, Gen. 3, "LM7", "LS4 front wheel drive V8" 
5.3L Vortec, 6.098" rod)
327 = 4.000" x 3.25" (Gen. 1, 5.7" rod)
345 = 3.893" x 3.622" ('97-later, Gen. 3, "LS1", 6.098" rod)
350 = 4.000" x 3.48" (Gen. 1, 5.7" rod)
350 = 4.000" x 3.48" ('96-'01, Gen. 1, Vortec, 5.7" rod)
350 = 3.900" x 3.66" ('89-'95, "LT5", in "ZR1" Corvette 32-valve DOHC, 
5.74" rod)
364 = 4.000" x 3.622" ('99-later, Gen. 3, "LS2", "LQ4" 6.0L Vortec, 6.098" rod)
376 = 4.065" x 3.622" (2007-later, Gen. 4, "L92", Cadillac Escalade, GMC Yukon)
383 = 4.000" x 3.80" ('00, "HT 383", Gen. 1 truck crate motor, 5.7" rod)
400 = 4.125" x 3.75" (Gen. 1, 5.565" rod)
427 = 4.125" x 4.00" (2006 Gen. 4, LS7 SBC, titanium rods)

Two common, non-factory small block combinations:
377 = 4.155" x 3.48" (5.7" or 6.00" rod) 400 block and a 350 crank with 
"spacer" main bearings
383 = 4.030" x 3.75" (5.565" or 5.7" or 6.0" rod) 350 block and a 400 crank, 
main bearing crank journals cut to 350 size


CHEVY BIG BLOCK V8 BORE AND STROKE

366T (tall deck) = 3.935" x 3.76"
396 = 4.096" x 3.76"
402 = 4.125" x 3.76"
427 = 4.250" x 3.76"
427T (tall deck) = 4.250" x 3.76"
454 = 4.250" x 4.00"
496 = 4.250" x 4.37" (2001 Vortec 8100, 8.1 liter)
502 = 4.466" x 4.00"
572T (tall deck) = 4.560" x 4.375" (2003 "ZZ 572" crate motor)

ALL production big blocks used a 6.135" length rod.


CHEVY 348-409 V8 BORE AND STROKE 

348 = 4.125" x 3.25" (6.125" rod)
409 = 4.312" x 3.50" (6.010" rod)
427 = 4.312" x 3.65" (6.135" rod), 1963 "Z11" SHP drag race


CHEVY SMALL BLOCK CRANKSHAFT JOURNAL SIZES

Gen. 1, "Small Journal"
265...Mains- 2.30", Rods- 2.00"
283...Mains- 2.30", Rods- 2.00"
302...Mains- 2.30", Rods- 2.00"
327...Mains- 2.30",  Rods- 2.00"


Gen. 1, "Medium Journal", includes Vortec 305 and 350 through '98
262...Mains- 2.45", Rods- 2.10"
267...Mains- 2.45", Rods- 2.10"
302...Mains- 2.45", Rods- 2.10"
305...Mains- 2.45", Rods- 2.10"
307...Mains- 2.45", Rods- 2.10"
327...Mains- 2.45", Rods- 2.10"
350...Mains- 2.45", Rods- 2.10"


Gen. 1, "Large Journal"
400...Mains- 2.65", Rods- 2.10"

Non-production Gen. 1 combination using Gen. 1 400 crank in Gen. 1 350 block
383...400 crank, Mains cut to 2.45", Rods- 2.10"

Non-production Gen. 1 combination, using Gen. 1 350 crank in Gen. 1 400 block
377..."Spacer" or "thick" main bearings with 350 crank, Rods- 2.10"

Gen. 2, "Medium Journal", includes "L-99" 265, "LT1" 350, "LT4" 350
265...Mains- 2.45", rods-2.10"
305...Mains- 2.45", Rods-2.10"
350...Mains-2.45", Rods-2.10"

Non-production Gen. 2 combination, using Gen. 2 265 "L-99" crank in Gen. 2 350 block
302...Mains- 2.45", Rods- 2.10"

Gen. 3, includes '97-2005 "LS1" Corvette, Firebird, Camaro
345...Mains- 2.558", Rods- 2.10"

Corvette "ZR1", DOHC, "LT5"
350...Mains- 2.76", Rods- 2.10"

CHEVY BIG BLOCK CRANKSHAFT JOURNAL SIZES

366T
396
402
427
427T
454
502
ALL Chevy big blocks used Mains- 2.7488"-2.7495", Rods- 2.20"

CHEVY W-ENGINE CRANKSHAFT JOURNAL SIZES

348
409
427 Z-11
All W-motors used Mains- 2.50", Rods- 2.20"
</pre>


[[Category:Identification and decoding]]
[[Category:Engine]]
[[Category:GM]]