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Author Topic:   ID# FOR SMALL CHEVY
TBONE
Dirt Roller

Total posts: 9
posted June 26, 2001 09:06 PM
I'M TRYING TO FIND OUT IF ANYONE KNOWS OF A WEB SITE THAT MIGHT HAVE THE ID LISTINGS FOR SMALLBLOCK CHEVY MOTORS.YHE ONE UNDER THE ALTERNATOR IS KO321CMR & THE ONE ON THE BACK OF THE BLOCK IS 3970010.IF ANYONE CAN HELP ME I WOULD GREATLY APPRECIATE IT.

sideways
Dirt Forum Racer

Total posts: 81
posted June 26, 2001 09:16 PM
I think the site is www.z28.com.That is the best one I have found I know if you go to google search and put in"chevy casting numbers"it should come up.Hope this helps.

Pickel
Dirt Freak

Total posts: 239
posted June 26, 2001 09:42 PM UIN: 25419780
try www.mortec.com it lists just about everything I checked the id# its a 350

TBONE
Dirt Roller

Total posts: 9
posted June 26, 2001 10:29 PM
THANKS FOR THE HELP.

jammin
Dirt Administrator

Total posts: 3279
posted June 27, 2001 01:43 PM UIN: 16262997
Your information is right here on the forum. If you will do a search with the casting number in the Engine Tech forum, you will find info about your part.

RK19
Dirt Newbie

Total posts: 2
posted June 27, 2001 05:50 PM
from the suffix code CMR
this is what i got out of my suffix code book
che 74 350 145hp 400 trans 1x2 intake vin h
cor 78 350 220hp 350 trans 1x4 intake vin 4
and this the casting #3970010....350...69-80...2 or 4
this seems to be the most commonly used block it is alittle heavier then others and i think has a higher nickel content

RK19
Dirt Newbie

Total posts: 2
posted June 27, 2001 05:53 PM
this is actually BK19 but my son registered and now when i sign on under BK19 it comes up as RK19

jammin
Dirt Administrator

Total posts: 3279
posted June 27, 2001 06:34 PM UIN: 16262997
Here ya go...see if this helps anyone. Now you can do a search for the casting number on the forum and it will bring you to this post.

jammin

Block Casting Numbers

This should help everyone out when looking for cores and verifying engines before buying.

Casting # CID Main Bolts
330817 400 2-Bolt
346236 454 2-Bolt
355909 262 2-Bolt
3703524 265 2-Bolt
3720991 265 2-Bolt
3731548 283 2-Bolt
3737739 283 2-Bolt
3751872 348 2-Bolt
3755011 348 2-Bolt
3756519 283 2-Bolt
3771705 348 2-Bolt
3782870 327 2-Bolt
3788068 409 2-Bolt
3789935 283 2-Bolt
3790721 283 or 327 2-Bolt
3791362 327 2-Bolt
3794226 283 2-Bolt
3795623 409 2-Bolt
3798962 348 2-Bolt
3830814 409 or 427 2-Bolt
3834810 283 2-Bolt
3834812 283 2-Bolt
3844422 409 2-Bolt
3849852 283 2-Bolt
3855961 396 2-Bolt
3855962 396 4-Bolt
3857656 409 2-Bolt
3858174 327 2-Bolt
3858180 327 2-Bolt
3862194 283 2-Bolt
3869942 427 2-Bolt or 4-Bolt
3892657 302 or 327 or 350 2-Bolt
3896944 283 2-Bolt
3902406 396 2-Bolt or 4-Bolt
3903352 327 2-Bolt
3904351 427 2-Bolt or 4-Bolt
3914636 307 2-Bolt
3914660 327 2-Bolt
3914678 302 or 327 or 350 2-Bolt
3916321 427 2-Bolt or 4-Bolt
3916323 396 2-Bolt or 4-Bolt
3932386 302 or 350 4-Bolt
3932388 302 or 350 4-Bolt
3935439 427 2-Bolt or 4-Bolt
3935440 396 2-Bolt or 4-Bolt
3946052 427 4-Bolt
3951509 400 2-Bolt or 4-Bolt
3951511 400 4-Bolt
3955270 427 2-Bolt or 4-Bolt
3955272 396 2-Bolt or 4-Bolt
3956618 302 or 327 or 350 2-Bolt or 4-Bolt
3956632 307 2-Bolt
3963512 427 or 454 2-Bolt or 4-Bolt
3969854 396 or 402 2-Bolt or 4-Bolt
3970010 350 2-Bolt or 4-Bolt
3970014 350 2-Bolt or 4-Bolt
3970020 307 2-Bolt
3970024 307 2-Bolt
3999289 454 2-Bolt
3999290 402 2-Bolt

Top 11 castings for stock production heads
# Part No. Good Points Bad Points
1 3782461X High Compression(57.5 cc), best ports of any OEM production cast iron head, intake runner volume 170-180 cc No Accessory Bolt Holes, rare, likely to be cracked, 2.02/1.60 versions are very rare.
2 3991492 '70 high-compression(62.1 cc), good ports, accessory bolt holes, 2.02/1.60-valve versions come with *****-in-studs and guideplates Close proximity of water jacket to spring pocket on 492's cast prior to 1972, requires special spring seat cutter if using larger than stock springs.
3 3890462 Ports similar to 461(#4, below), but a little better combustion chamber shape. More common than 461 and 461X, but still rare; no accessory bolt holes.
4 3782461 Similar to 461X but with smaller intake port Still rare, probably cracked, no accessory bolt holes.
5 3927186 '64 to '70(average chamber volume 64cc) '69 and '70 have accessory bolt holes. Rare, valvespring seats in close proximity to the water jacket.
6 3947041 '69 350/300hp, good chamber(similar to 462), accessory bolt holes. Very rare, valvespring seats in close proximity to the water jackets.
7 3932441 '69-'70, large chamber(73 cc) some versions have steam holes for 400, ports decent, accessory bolt holes. No 2.02/1.60 valve factory made versions
8 3973487 '71 76cc, like 441, but a little better chamber, hardened seats for unleaded gas, accessory bolt holes. Big chamber requires popup pistons to acheive race high compression.
9 3998993 '71-'76 US/'85-'88 Goodwrench Mexico..similar to 487, widely available Big chamber requires popup pistons to acheive race high compression.
10 332882 '71-'76, 350/400, big chamber/low-compression, accessory bolt holes, hardened seat This head changed the intake port design; ports became progressively poorer; this casting is the best of the worst.
11 462624 '76-'78, 305, 58 cc chamber 1.84/1.50 valves, hardened seats, accessory bolt holes; the most desirable 305 head. 1.84/1.50 valves and ports too small for use on larger displacement engines. Accepts 1.94/1.50 by reworking the seats.


Identification Markings
Symbols Typical Casting Numbers Description
Rectangle 460 '55 and up 265/283 low compression(8:1), 1.72/1.50 valves.
Narrow Triangle over Rectangle 520/896 '58 and up 283 Power Pack/'57-'60 fuel injection, 9.25:1 CR, 1.72/1.50 valves, 59cc chamber, could be good replacement on late 305 engine, but has no accessory bolt holes.
Vertical Bar over Rectangle 997 '57 Corvette 270 hp/9.5 to 1 CR: Chamber similar to power pack, but with sharp edges in plug/shroud area.
2 Vertical Bars over Rectangle 997 '56 Corvette 2X4 barrel...283/'58 pass car FI; chamber same as '57 270 hp Corvette
Large Camel Humps 291,461, 461X, 462 Original high performance/fuelie heads 1.94/1.50 or 2.02/1.60 valves available. 62-64cc chambers
Left Facing Right Triangle 041 '69-'70 350/300hp, accessory bolt holes, most have 1.94/1.50 valves.
Small Camel Humps 186,492 Some 186 and all 492 have accessory bolt holes. 1.94/1.50 or 2.02/1.60 valves available. 64cc chambers
Large Triangle over Rectangle("crown") 882 Large Chamber (76 cc, hardened exhaust seats, compromised intake port....('71-'76 350/400)
None 113 '88-'90/present 350 HO aluminum, no exhaust heat, 58 cc chamber, 1.94/1.50 valves, centerbolt valve covers, good street head.
3-Right Facing "stairs" on end of each head, "bench" on intake runner 487 '71-'76 76 cc combustion chamber..best large chamber head, 1.94 and 2.02's available, latter machined for *****-in-studs and guideplates
Right Facing Bench 993 Common Big Chambered Head, not a lightweight casting.
1 triangle 882 alternate marking for 882
2 trianges 624 late model 305 head, conventional valve covers, intake not restricted
"Saddle" and seperate bar 416 Late Model 305, conventional valve covers, intake port on restricted.
Double("captain's") bars 193 Mid 80's style centerbolt cover with restrictor vane cast into the intake port. Not recommended for high performance use.


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