Block stamp opinions please?
Melting Slicks
Joined: Mar 2002
Posts: 2,140
Likes: 7
From: Ohio
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.
Thread Starter
Heel & Toe
Joined: Dec 2006
Posts: 24
Likes: 0
From: Norman OK
The G58 was on the block, passengers side, by the starter.
Team Owner
Joined: Aug 2000
Posts: 21,455
Likes: 462
From: Massillon,Ohio USA
2020 C3 of the Year Finalist - Unmodified
Cruise-In VI Veteran
St. Jude Donor '08-'09-'10-'11-'12
...I've know of one original '71 454 that was built 12/7/70 and it's 454 has a block date of 4/8/70 and it is on an original one-owner car. I myself have seen it & believe it to be real also. All it's numbers line up too.
...what bothers me more on the original poster's car is the head dates VS assembly date of the engine. Can a head itself be cast, machined, prepped & assembled on the EXACT same day as the motor was assembled??????????????????????
Melting Slicks
Joined: Mar 2002
Posts: 2,140
Likes: 7
From: Ohio
...I've know of one original '71 454 that was built 12/7/70 and it's 454 has a block date of 4/8/70 and it is on an original one-owner car. I myself have seen it & believe it to be real also. All it's numbers line up too.
...what bothers me more on the original poster's car is the head dates VS assembly date of the engine. Can a head itself be cast, machined, prepped & assembled on the EXACT same day as the motor was assembled??????????????????????
...what bothers me more on the original poster's car is the head dates VS assembly date of the engine. Can a head itself be cast, machined, prepped & assembled on the EXACT same day as the motor was assembled??????????????????????
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
Sometimes 6's, 8's, 9's, and 0's can be difficult to distinguish on casting dates, so you might take another look at the head casting dates to double-check them. If your car is not an original factory creation, it is a very well done "clone". I'm leaning toward original, myself. The engine stamp is really no big deal. Paint can get into the stamped lettering just from someone getting some touch-up engine paint overspray on the pad then wiping it off; that leaves some paint in the lettering and that's what it looks like to me. If the head casting dates and car build date can not be resolved, it would appear that, at least, the heads have been replaced (with 'legitimate' factory replacements).
Thread Starter
Heel & Toe
Joined: Dec 2006
Posts: 24
Likes: 0
From: Norman OK
I agree 100% ...
... and you should get better pictures also. The last enlarged picture of the serial number appears as though the broach marks were applied AFTER the stamp (see the lines running through the 9 and S ... but the picture is not clear enough to be definitive)
I assume the K228 rear cast date is the rear differential ... ???
Trim tag C21 - I think this is really G21 (C21 is Oct 21, 1968 and G21 is Feb 21, 1969)
... and you should get better pictures also. The last enlarged picture of the serial number appears as though the broach marks were applied AFTER the stamp (see the lines running through the 9 and S ... but the picture is not clear enough to be definitive)
I assume the K228 rear cast date is the rear differential ... ???
Trim tag C21 - I think this is really G21 (C21 is Oct 21, 1968 and G21 is Feb 21, 1969)
Trim tag is G21, not C21.
Here are photos of the block cast date and the head dates. The "G" on the block is very hard to read, but if it is not a G, what else could it be? The A27 head looks like the last number could possibly be an 8 instead of a 9, same on the A28 head.
Team Owner
Joined: Sep 2006
Posts: 31,237
Likes: 4,330
From: Westminster Maryland
As was mentioned, Al Grenning can put every one's mind at ease. For just some $$$. I believe when he makes a determination you don't have to put knowledgeable in quotation marks.
Regards,
Alan
Regards,
Alan
Instructor
Joined: May 2007
Posts: 112
Likes: 1
From: Chadds Ford PA
The broach marks look heavy to me. Also, many of the left stamps on big blocks are skewed due to the plug in the head, as the head was on when the stamp was made. Your's is straight and looks close to the plug in the head.
All you're going to get here or anywhere else are opinions. The only way you're ever going to know for sure is to pull the head and compare the consistency of the broach marks. I'd pull the head, clean up the block and take a lot of pictures. That way, if it's original, the issue is put to bed. The photographs will be worth more than anyone's opinion when it comes time to sell it.
I just saw a 69 tri-power car at the local Corvette place for sale for 129K. That's a lot of motivation to play with the numbers. I hope your's is original. If it was me, I'd want to know for sure.
All you're going to get here or anywhere else are opinions. The only way you're ever going to know for sure is to pull the head and compare the consistency of the broach marks. I'd pull the head, clean up the block and take a lot of pictures. That way, if it's original, the issue is put to bed. The photographs will be worth more than anyone's opinion when it comes time to sell it.
I just saw a 69 tri-power car at the local Corvette place for sale for 129K. That's a lot of motivation to play with the numbers. I hope your's is original. If it was me, I'd want to know for sure.
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Race Director
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Big blocks were stamped before the head was put on. That's why it's on the left (to leave room for the VIN) and why the stamp is frequently observed to be 'underneath' the plug, very close the head.