Block stamp opinions please?
Thread Starter
Heel & Toe
Joined: Dec 2006
Posts: 24
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From: Norman OK
Block stamp opinions please?
Can someone tell me if this block stamp looks legit on this 1969 Corvette? I was told that the stamp looks ok but that it does not fall within an acceptable date range for the block cast date which is G58. From what I understand the block casting date is July 5, 1968, the engine build date is January 28, 1969 (T0128LR) . Would it be unusual or impossible for there to be this much time between casting and build dates?
Thread Starter
Heel & Toe
Joined: Dec 2006
Posts: 24
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From: Norman OK
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Getting a block several months older than the vehicle build date is not impossible [i.e.; defective block sent to repair area and got set aside until inventory time]...but it is improbable. Stranger things have happened, and since your block and stamp appear to be legitimate, I'd just let NCRS folks "have fun" evaluating it if you enter one of their events.
Burning Brakes
Joined: Oct 2006
Posts: 1,089
Likes: 43
From: Native Californian CALIFORNIA
Army
I can see you partial VIN. I would strongly suggest you get a fact book as my records indicate the last January 69 VIN ended with 714695 and the last February VIN was 717571.
If this is correct your January 28, 1969 build date is in question. Books with production dates with corresponding VINs are readily available.
Best of luck to you
If this is correct your January 28, 1969 build date is in question. Books with production dates with corresponding VINs are readily available.
Best of luck to you
Thread Starter
Heel & Toe
Joined: Dec 2006
Posts: 24
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From: Norman OK
I believe I have seen the production information you are talking about and I have pasted it below, but I thought the sequence numbers were the Beginning numbers, not Ending numbers. Can someone clarify for me? Also, on the following chart, are the letter codes referring to the casting dates or the engine build dates??
1969 Corvette Production
16,633 Convertibles + 22,129 Coupes = 38,762 Total Production for 1969
Code Month Production Sequence #
1969 Corvette Production
16,633 Convertibles + 22,129 Coupes = 38,762 Total Production for 1969
Code Month Production Sequence #
- B September '68... 3,041..... 703041
- C October........... 3,231..... 706272
- D November........ 2,887..... 709159
- E December........ 2,583..... 711742
- F January '69...... 2,953..... 714695
- G February......... 2,876..... 717571
- H March............. 2,972..... 720543
- I April ................. 772..... 721315
- J May................... 0.....
- K June................2,059..... 723374
- L July..................2,501..... 725875
- M August.............2,232..... 728107
- N September .......2,856..... 730963
- O October...........3,104..... 734067
- P November ........2,731..... 736798
- Q December '69....1,964..... 738762
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Burning Brakes
Joined: Oct 2006
Posts: 1,089
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From: Native Californian CALIFORNIA
Army
On your production numbers the final serial number produced for that month is listed. The end of the run and not the start of production. Look at the first month of production, it shows that approximately 3,041 cars were produced.
Team Owner
Joined: Sep 2006
Posts: 31,227
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From: Westminster Maryland
I know that the Broach Marks really varied as the tool became duller from use. I've never seen Broach Marks that distinct on a pad that I thought was original. I've looked at a tiny percentage of production, so my observation and conclusion is flawed at best.
Regards,
Alan
Regards,
Alan
Melting Slicks
Joined: Mar 2002
Posts: 2,140
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From: Ohio
I know that the Broach Marks really varied as the tool became duller from use. I've never seen Broach Marks that distinct on a pad that I thought was original. I've looked at a tiny percentage of production, so my observation and conclusion is flawed at best.
Regards,
Alan
Regards,
Alan
Thread Starter
Heel & Toe
Joined: Dec 2006
Posts: 24
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From: Norman OK
Here is the deck stamp from another/closer view. This is a 37k mile survivor car and the engine (or anything else for that matter) does not appear to have ever been removed. I've owned the car for 2 years and the person I bought it from had it in his collection for 14 years. There have been several "knowledgable" people look at the stamp and everyone thinks it looks legit, no restamp. I only wish I could find some logical explanation for the dates...
Thread Starter
Heel & Toe
Joined: Dec 2006
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From: Norman OK
T0128LR = Tonawanda January 28 427/435/mt
19S717004 = February 24, 1969 car build date
What is the block casting number?? (driver side, rear - 3904351 or 3916321?)
Do you have a picture of the casting date?? (I understood Tonawanda blocks to have a double digit year code ... ie: G568)
19S717004 = February 24, 1969 car build date
What is the block casting number?? (driver side, rear - 3904351 or 3916321?)
Do you have a picture of the casting date?? (I understood Tonawanda blocks to have a double digit year code ... ie: G568)
Burning Brakes
Joined: Oct 2006
Posts: 1,089
Likes: 43
From: Native Californian CALIFORNIA
Army
It is evident that the block was repainted at one time or another as there is paint in the stampings, this would not be if not repainted.
What does your trim tag state for a build date?
Pull your valve covers and look at the head dates, or the rearend date code as these are indicators. There are numerous areas you will find date codes.
All this will help or hurt your case in regards to the VIN vs build date issue you are experiencing.
What does your trim tag state for a build date?
Pull your valve covers and look at the head dates, or the rearend date code as these are indicators. There are numerous areas you will find date codes.
All this will help or hurt your case in regards to the VIN vs build date issue you are experiencing.
Burning Brakes
Joined: Oct 2006
Posts: 1,089
Likes: 43
From: Native Californian CALIFORNIA
Army
All 427s in 68 and around ro S/N 20,000 in 1969 have the casting date on the passenger's side of the block near the freeze plug and engine mount in front of the starter. After about S/N 20,000 in 1969 the date on a 427 is on the same place as a small block, that being passenger's side of the engine on top of the transmission bell housing mounting flange (opposite the casting number)
Casting date is an alphanumeric code (example: A279= January 27, 1969. The engine casting date must precede the engine assembly date and both must precede the vehicle assembly date.
Casting date is an alphanumeric code (example: A279= January 27, 1969. The engine casting date must precede the engine assembly date and both must precede the vehicle assembly date.
Thread Starter
Heel & Toe
Joined: Dec 2006
Posts: 24
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From: Norman OK
Got the numbers today, saw them all with my own eyes. Here's what I've got:
1969 Convertible 427/435 Tri Power 4-sp
Block Cast Date: G58
Block Cast Number: 3935439
Rear Cast Date: K228
Head Casting: 3919840
Heads Dates: A 28 9 & A 27 9
Block Pad: T0128LR 19S717004
Trim Tag Date: C21
Infomation on the tank sticker is:
Order #AY0204
Date Received: 9/01/17
Exp Date of Prod: 9/00/00
How do the numbers stack up? I am no expert on this stuff by any means and I truly appreciate everyone's input. Would it be possible, or does anyone know, as I have read somewhere, that as they cast these blocks they set them aside until needed and then pulled them in a "first in, last out" sequence? If this block was cast and then several more piled up in front of it maybe that could explain why it set for so long before being used? Maybe I'm grasping at straws, but for obvious reasons I want to know whether it is, or is not, impossible for this to be the original block for my car.
1969 Convertible 427/435 Tri Power 4-sp
Block Cast Date: G58
Block Cast Number: 3935439
Rear Cast Date: K228
Head Casting: 3919840
Heads Dates: A 28 9 & A 27 9
Block Pad: T0128LR 19S717004
Trim Tag Date: C21
Infomation on the tank sticker is:
Order #AY0204
Date Received: 9/01/17
Exp Date of Prod: 9/00/00
How do the numbers stack up? I am no expert on this stuff by any means and I truly appreciate everyone's input. Would it be possible, or does anyone know, as I have read somewhere, that as they cast these blocks they set them aside until needed and then pulled them in a "first in, last out" sequence? If this block was cast and then several more piled up in front of it maybe that could explain why it set for so long before being used? Maybe I'm grasping at straws, but for obvious reasons I want to know whether it is, or is not, impossible for this to be the original block for my car.
Race Director
Joined: Jul 2001
Posts: 15,892
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The unusual dates are not unheard of, but rare enough to cause suspicion. Each of the photographs reveals an unusual pad surface with respect to the broach marks.
If you are interested enough and convinced that it is not a restamp, please contact Al Grenning to have a professional evaluation done. In addition to having an experienced eye, he maintains a huge database of stamp pads. He may have records of cars close in S/N to yours and be able to explain the sequence of events.
If you are interested enough and convinced that it is not a restamp, please contact Al Grenning to have a professional evaluation done. In addition to having an experienced eye, he maintains a huge database of stamp pads. He may have records of cars close in S/N to yours and be able to explain the sequence of events.
1st Gear
Joined: Feb 2008
Posts: 1
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I had my block re-stamped when the previous owner had the engine rebuilt and forgot to tell the rebuilders not to deck the block. Three of my serial numbers remained faintly on the pad so we could see that it was the original engine, but we wanted all the numbers to show. I contacted a judge in the NCRS who had a stamp and rented it to us to re-stamp the block. He verified all the numbers and the re-stamp looks good. Possibly this was done to your car without particular attention to the build dates.
You're joking, right!?? 