C3 General General C3 Corvette Discussion not covered in Tech
Sponsored by:
Sponsored by:

Did I de-code this right?

Thread Tools
 
Search this Thread
 
Old Jun 14, 2005 | 03:29 PM
  #1  
87bob's Avatar
87bob
Thread Starter
Melting Slicks
20 Year Member
Veteran: Coast Guard
Liked
Loved
 
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Default Did I de-code this right?

350 Engine Block #3970010

F0413CKB

F=Flint
04=April
13=13th day
CKB=Not listed in the Corvette Engine suffix. Listed in the Camaro engine listing, but Camaros were never built in St. Louis (see VIN below)

12S253152

1=Chevy
2=1972
S=St. Louis
253152=Vin#

Any light you can shed on this is appreciated!
THANKS
Reply
Old Jun 16, 2005 | 07:25 AM
  #2  
87bob's Avatar
87bob
Thread Starter
Melting Slicks
20 Year Member
Veteran: Coast Guard
Liked
Loved
 
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Default

37 views and no help. I'm I the only one trying to decode manufacturing information?
Reply
Old Jun 16, 2005 | 07:46 AM
  #3  
Tomi72's Avatar
Tomi72
Racer
20 Year Member
 
Joined: Nov 2000
Posts: 369
Likes: 1
From: Finland
Default

According to "Chevrolet by the numbers" book the CKB suffix was used in -72 to denote a 165 hp passenger car engine (with th350 or th400). In -73 the same code was used on Camaros (175hp with 4 speed). This would explain the St. Louis assembly plant.

I think everything else is decoded right

rgds Tomi

Last edited by Tomi72; Jun 16, 2005 at 12:06 PM.
Reply
Old Jun 16, 2005 | 08:01 AM
  #4  
Nascar5085's Avatar
Nascar5085
Burning Brakes
10 Year Member
 
Joined: Feb 2005
Posts: 1,216
Likes: 0
From: Blue Springs Missouri
St. Jude Donor '06
Default

I found this on a website. Looks like that casting number was used on different sizes of motors.


3970010....302.....69....4...Z-28 Camaro
3970010....327.....69....2...Trucks and industrial
3970010....350...69-80...2 or 4
Reply
Old Jun 16, 2005 | 11:43 AM
  #5  
lg4vette's Avatar
lg4vette
Instructor
 
Joined: May 2005
Posts: 208
Likes: 0
From: West Branch MI
Default

The block currently in our '80 (non-original) is also stamped 3970010. I looked it up online and found that code was used on 1969 to 1979 350's with 2 or 4 bolt mains. Not sure of the other code.....can't really say I know where to look for it on the engine.
Reply
Old Jun 16, 2005 | 12:23 PM
  #6  
Mike Ward's Avatar
Mike Ward
Race Director
10 Year Member
 
Joined: Jul 2001
Posts: 15,892
Likes: 42
Default

Originally Posted by 87bob
37 views and no help. I'm I the only one trying to decode manufacturing information?
You've neglected to provide the casting date of the engine block which would make narrowing down which type of car it came from much easier.

Also, you cannot decode the VIN partial stamping on the block in the same manner as the complete VIN number shown in the windshield frame.
Reply
Old Jun 16, 2005 | 01:11 PM
  #7  
Tom73's Avatar
Tom73
Race Director
25 Year Member
Active Streak: 120 Days
All Eyes On Me
Liked
 
Joined: Apr 1999
Posts: 15,133
Likes: 477
From: NM
Default

Originally Posted by 87bob
350 Engine Block #3970010

F0413CKB

F=Flint
04=April
13=13th day
CKB=Not listed in the Corvette Engine suffix. Listed in the Camaro engine listing, but Camaros were never built in St. Louis (see VIN below)

12S253152

1=Chevy
2=1972
S=St. Louis
253152=Vin#

Any light you can shed on this is appreciated!
The 3970010 block is a VERY common block used from '69 through '80 in Vettes and all kinds of other Chevy/GM cars and trucks.

F0413CKB is decoded correctly. F=Flint; 04=April; and 13=13th day
The CKB can be an issue. It was used three times:

1972 as a 350/165hp automatic with 2 bbl carb in the A & B bodies;
1973 as a 350/175hp manual trans with 4 bbl card in the F, A, X, and Monte Carlo bodies
1974 as a 350/185hp with manual trans and 4 bbl card in the F & X bodies

But my concern is the "F" for Flint. The F designation was changed to "V" starting with the 1967 production. So a stamp with F would indicate a 1966 or earlier engine.

So we have a pre '66 engine with a '72/'73/'74 usage suffix on a 69-80 block. Something is just not right. Are you sure that you are reading the numbers correctly? If so, then I would have to assume that the engine has been restamped.

There is also trouble with the VIN deritive, 12S253152
For a '72 Vette this should be 12S500001 - 12S527004
The number after the S should be a 5. Then you have your build sequence, which show # 53,152 in this case, but only 27,004 Vettes were built for '72.

tom...

Last edited by Tom73; Jun 16, 2005 at 01:20 PM.
Reply
Old Jun 16, 2005 | 02:54 PM
  #8  
87bob's Avatar
87bob
Thread Starter
Melting Slicks
20 Year Member
Veteran: Coast Guard
Liked
Loved
 
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Default

The Casting date is B22 which I read as February 2nd 1972. Some have speculated that the "F" is a problem and I quote

"But my concern is the "F" for Flint. The F designation was changed to "V" starting with the 1967 production. So a stamp with F would indicate a 1966 or earlier engine."

On page 65 of Corvette by the numbers the "F"=Flint was still used but only for Flint Motor Facility. No Corvette Engines were built at this plant so Tom73 is right it is not a Corvette engine.

Since the V.I.N. shows the "S" for St. Louis can anyone tell me beside the Corvette what else G.M. built in St. Louis in 1972?
Since it is not a Corvette engine it had to come from a passenger car or pickup.

Thanks for your help.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-1

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-2

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-3

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-4

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-5

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-6

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-7

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
story-8

5 MOST and 5 LEAST Popular Corvette Model Years in History!

 Joe Kucinski
story-9

2027 Corvette Buyer's Guide: Everything You Need to Know!

 Joe Kucinski
Old Jun 16, 2005 | 02:59 PM
  #9  
427basketcase's Avatar
427basketcase
Drifting
15 Year Member
 
Joined: May 2002
Posts: 1,546
Likes: 5
From: Sacramento California
Default

I think the problem here is confusing "Casting" (raised) numbers with "Stamped" (indented) numbers. The stamped number contains no manufacture date information other than a year cross-reference from the suffix. You need to check THIS website for the "Casting" locations, and then you can determine the assembly plant, and date of build. Then reference the "Stamped" numbers for the suffix to determine the application, the numbers behind the suffix are VIN derivative of the car the block came out of and really contain no information at all.

Last edited by 427basketcase; Jun 16, 2005 at 03:04 PM.
Reply
Old Jun 16, 2005 | 03:26 PM
  #10  
87bob's Avatar
87bob
Thread Starter
Melting Slicks
20 Year Member
Veteran: Coast Guard
Liked
Loved
 
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Default

Thanks, I am working out of "Corvette by the Numbers" and "Chevy V-8 Engine Casting Numbers".

The information I supplied in the first post is the stamped numbers on the front passenger side pad except for the block number (3970010) cast above the oil filter pad.

The B22 date code number on the oppsite side from the block number above where the bellhousing mounts.

As of now the only thing I don't know is what other car/truck lines were made in St. Louis in 1972. I was unaware of any other models made in St.Louis I though it was just Corvettes.

Last edited by 87bob; Jun 16, 2005 at 03:28 PM.
Reply
Old Jun 16, 2005 | 04:34 PM
  #11  
Tom73's Avatar
Tom73
Race Director
25 Year Member
Active Streak: 120 Days
All Eyes On Me
Liked
 
Joined: Apr 1999
Posts: 15,133
Likes: 477
From: NM
Default

Originally Posted by 87bob
As of now the only thing I don't know is what other car/truck lines were made in St. Louis in 1972. I was unaware of any other models made in St.Louis I though it was just Corvettes.
St Louis had multiple assembly plants at one time. Believe some Camaros and some full size were built there but am not sure. May some history expert can advise.

tom...
Reply
Old Jun 16, 2005 | 04:39 PM
  #12  
lg4vette's Avatar
lg4vette
Instructor
 
Joined: May 2005
Posts: 208
Likes: 0
From: West Branch MI
Default

So is the 3970010 casting correct for an '80? If so, I'm going to stay with that and not try to find a "correct" LG4 for our car!
Reply
Old Jun 16, 2005 | 04:56 PM
  #13  
Tom73's Avatar
Tom73
Race Director
25 Year Member
Active Streak: 120 Days
All Eyes On Me
Liked
 
Joined: Apr 1999
Posts: 15,133
Likes: 477
From: NM
Default

Originally Posted by lg4vette
So is the 3970010 casting correct for an '80? If so, I'm going to stay with that and not try to find a "correct" LG4 for our car!
An 80 used three different blocks, the 370010 for the L48 and L82, the 14010207 also for the L48 and L82 but in limited production, and the 4715111 for the LG4 (the 180hp 305ci Calif engine).

tom...
Reply
Old Jun 16, 2005 | 07:08 PM
  #14  
Tom73's Avatar
Tom73
Race Director
25 Year Member
Active Streak: 120 Days
All Eyes On Me
Liked
 
Joined: Apr 1999
Posts: 15,133
Likes: 477
From: NM
Default

Originally Posted by 87bob
On page 65 of Corvette by the numbers the "F"=Flint was still used but only for Flint Motor Facility. No Corvette Engines were built at this plant so Tom73 is right it is not a Corvette engine.
87bob, all Corvette small blocks came from the Flint factory. They used the "F" of the stamp pad through 1966 and then went to a "V" for 1967. That is the problem with it having an F, it would have to be a '66 or earlier engine for that to be correct.

Originally Posted by 427basketcase
.... The stamped number contains no manufacture date information other than a year cross-reference from the suffix.
The assembly date is stamped on the stamp pad as part of the engine usage suffix. In this case the F0422CDX, the 0422 is the assembly date. April 22nd. Now the year is not stamped there, would need the casting date for that. But the numbers are not adding up on this one.

tom...
Reply
Old Jun 17, 2005 | 02:57 PM
  #15  
87bob's Avatar
87bob
Thread Starter
Melting Slicks
20 Year Member
Veteran: Coast Guard
Liked
Loved
 
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Default

Originally Posted by Tom73
87bob, all Corvette small blocks came from the Flint factory. They used the "F" of the stamp pad through 1966 and then went to a "V" for 1967. That is the problem with it having an F, it would have to be a '66 or earlier engine for that to be correct.


The assembly date is stamped on the stamp pad as part of the engine usage suffix. In this case the F0422CDX, the 0422 is the assembly date. April 22nd. Now the year is not stamped there, would need the casting date for that. But the numbers are not adding up on this one.

tom...
Ok I'll try this again.

Block casting number 3970010
Date code B22
V.I.N. 12S253152
Engine code F0413CKB

Per "Corvette by the numbers" page 78.

Block Casting Number=3970010 found above the oil filter used 1969-1979 as a 350CID used in various passenger cars and trucks, also used as a 302CID in 1969 Camaro

Casting Date code B22 found adjacent to the bell housing on the passenger side of the rear of the block. the B22 is a cast number above the bell housing on the passenger side. B=February 2=2nd day of the month 2=1972

On page 65 of Corvette by the numbers it states for the years 1970-1974 V=Flint and F=Flint Motor Facility (no Corvette engines produced at this plant). So it is safe to say this is not a Corvette block. Only the plant desiginated as "F"=Flint produced the Corvette Engines.

The partial V.I.N. stamped on the front of the block has to be read in reverse the last six digits are 253152 and they are the sequence number. The "S" in front of that is the vehicle build plant. The 2 in front of the build plant is the year. The first digit should be an engine code for a particular car/truck line.

So the only items I'm not clear on are:

The first digit of the V.I.N.
What car or truck this engine came from.

If I could find out for sure what else beside Corvettes were built in St. Louis in 1972 it would make sorting this out easier.

Thanks for all your input and help.
Bob
Reply
Old Jun 18, 2005 | 12:22 AM
  #16  
87bob's Avatar
87bob
Thread Starter
Melting Slicks
20 Year Member
Veteran: Coast Guard
Liked
Loved
 
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Default

Ttt
Reply
Old Jun 18, 2005 | 05:07 PM
  #17  
87bob's Avatar
87bob
Thread Starter
Melting Slicks
20 Year Member
Veteran: Coast Guard
Liked
Loved
 
Joined: Mar 2003
Posts: 2,512
Likes: 49
From: Franklin IN
Default

Ttt
Reply

Get notified of new replies

To Did I de-code this right?





All times are GMT -4. The time now is 09:02 AM.

story-0
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-1
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-2
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-3
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-4
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-5
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-6
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-7
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-8
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-9
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE