C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

1970 engine block pad stamp question

Thread Tools
 
Search this Thread
 
Old 08-04-2013, 07:45 PM
  #1  
Vetterbegood
Advanced
Thread Starter
 
Vetterbegood's Avatar
 
Member Since: Jun 2011
Location: Louisville KY
Posts: 61
Received 1 Like on 1 Post

Default 1970 engine block pad stamp question

Hi
Need some thoughts from the techies on the forum. On fleabay there is a 1970 350/350 coupe for sale. Owner states the block code CTJ has the J stamped backwards from the factory.... I have thought about this and don't see how it could happen since the only way I can think of is by modifying a "U" stamp to get this result.
Anyone seen this anomaly before ?
Any thoughts from you guys ?
Thanks, Keith
http://i1352.photobucket.com/albums/...1374010148?534
Old 08-04-2013, 08:12 PM
  #2  
Alan 71
Team Owner
 
Alan 71's Avatar
 
Member Since: Sep 2006
Location: Westminster Maryland
Posts: 30,173
Likes: 0
Received 2,878 Likes on 2,515 Posts

Default

Hi Keith,
I thought something similar to you when I saw the 'J'.
There's no way for it to be 'backward' and look like that. If ANYTHING it could have been upside down, but I don't think that could happen either... I think the individual stamps could only go in the gang-holder in one way.
If the 'J' had been stamped separately it could have been upside down, but there's no way to make it mirror image... it's a stamp... it only makes a single impression... it can't vary. it's either right side up or upside down.
I think the seller thought he had a simple explaination that no one would consider on their own.
Regards,
Alan
Old 08-04-2013, 08:28 PM
  #3  
DC3
Melting Slicks
 
DC3's Avatar
 
Member Since: Apr 2001
Location: Lubbock Texas
Posts: 2,024
Received 353 Likes on 254 Posts

Default

Originally Posted by Vetterbegood
Any thoughts from you guys ?
Thanks, Keith
http://i1352.photobucket.com/albums/...1374010148?534




To me, it looks like a "U" that just wasn't stamped clean.

DC
Old 08-04-2013, 08:48 PM
  #4  
7T1vette
Team Owner
 
7T1vette's Avatar
 
Member Since: Jan 2006
Location: Crossville TN
Posts: 36,600
Received 2,715 Likes on 2,273 Posts

Default



The stamping is deeper on the left side, and gradually lessens going to the right. With a gang-stamp, and a right-handed line worker, the right part of the "U" never got enough ooomph! to put an impression in the block.

At first, I thought a dyslexic [but creative] employee might have ground-off the {wrong} side of the U to create a J. But, now I think not....
Old 08-04-2013, 09:04 PM
  #5  
Alan 71
Team Owner
 
Alan 71's Avatar
 
Member Since: Sep 2006
Location: Westminster Maryland
Posts: 30,173
Likes: 0
Received 2,878 Likes on 2,515 Posts

Default

Hi,
Would CTU make this an LT-1.... but then it has a/c....?
Regards,
Alan
Old 08-04-2013, 09:31 PM
  #6  
whitehause
Pro
 
whitehause's Avatar
 
Member Since: Jun 2009
Location: Fleetwood PA
Posts: 613
Likes: 0
Received 3 Likes on 3 Posts

Default

That should be an O that never got stamped all the way.
As Alan said about the stamps, no way it's a backwards J it has to be a O. It sure ends at the top left like a U though. Maybe a factory mess up

CTO is a 350/350 4sp A/C so it is the right engine. I'm not to far from there, but If I brought a 3rd Vette project home home I'd be dead
But man would that be a cool one.

Last edited by whitehause; 08-04-2013 at 09:35 PM.
Old 08-04-2013, 09:38 PM
  #7  
Vetterbegood
Advanced
Thread Starter
 
Vetterbegood's Avatar
 
Member Since: Jun 2011
Location: Louisville KY
Posts: 61
Received 1 Like on 1 Post

Default

Alan
Yes a CTU is an LT-1, which doesn't make sense as VIN is correct.... That would be a half restamp ! Or it is an actual mistamp from factory, which I haven't seen before, but it's possible. Not a bad car to put back together which I can do, but this is weird and not sure I want to explain it to someone else.
Not going to loose sleep but I am puzzled.
Thanks, Keith
Old 08-04-2013, 09:40 PM
  #8  
whitehause
Pro
 
whitehause's Avatar
 
Member Since: Jun 2009
Location: Fleetwood PA
Posts: 613
Likes: 0
Received 3 Likes on 3 Posts

Default

The more I look at that, the more it looks like a mis-stamped U, I wonder if the guy at the factory grabbed the U instead of the O (they probably look close at a glance) and never fixed or noticed the error.
Old 08-04-2013, 09:40 PM
  #9  
Vetterbegood
Advanced
Thread Starter
 
Vetterbegood's Avatar
 
Member Since: Jun 2011
Location: Louisville KY
Posts: 61
Received 1 Like on 1 Post

Default

Originally Posted by whitehause
That should be an O that never got stamped all the way.
As Alan said about the stamps, no way it's a backwards J it has to be a O. It sure ends at the top left like a U though. Maybe a factory mess up

CTO is a 350/350 4sp A/C so it is the right engine. I'm not to far from there, but If I brought a 3rd Vette project home home I'd be dead
But man would that be a cool one.
Problem is he has a POP that is CTJ, hard to explain..... Thanks
Old 08-04-2013, 09:51 PM
  #10  
whitehause
Pro
 
whitehause's Avatar
 
Member Since: Jun 2009
Location: Fleetwood PA
Posts: 613
Likes: 0
Received 3 Likes on 3 Posts

Default

CTJ replaced the CTO engine code during the production year. If the POP was stamped CTJ, it would still be correct for a CTO car as it was just a clerical change for the same motor/trans/Air option. So it could be three "mistakes" on the same car.
Old 08-04-2013, 10:11 PM
  #11  
7T1vette
Team Owner
 
7T1vette's Avatar
 
Member Since: Jan 2006
Location: Crossville TN
Posts: 36,600
Received 2,715 Likes on 2,273 Posts

Default

Very possible.... on Friday afternoon or Monday morning.
Old 08-05-2013, 08:23 PM
  #12  
deejaydu
Safety Car
 
deejaydu's Avatar
 
Member Since: Mar 2007
Location: Blairsville , Georgia
Posts: 4,145
Received 480 Likes on 337 Posts

Default Ctj

Let me help to clear things up. I also own a 350/350hp factory A/C with power steering but in a convertible. It also has the reverse "J" stamped on the pad identical to the pictures that have been posted. It also raised a question with me before I bought the car however, my car has an Al Greening certification and a letter from Al Greening with it explaining the whole reverse "J" anomaly that is factory correct on very few cars for the 1970 model year. I will pull that letter and certification and repost later quoting directly from Al to explain this occurrence. My Vin # and this cars Vin # are close together.

I will be back shortly.
Old 08-05-2013, 08:38 PM
  #13  
whitehause
Pro
 
whitehause's Avatar
 
Member Since: Jun 2009
Location: Fleetwood PA
Posts: 613
Likes: 0
Received 3 Likes on 3 Posts

Default

Originally Posted by deejaydu
Let me help to clear things up. I also own a 350/350hp factory A/C with power steering but in a convertible. It also has the reverse "J" stamped on the pad identical to the pictures that have been posted. It also raised a question with me before I bought the car however, my car has an Al Greening certification and a letter from Al Greening with it explaining the whole reverse "J" anomaly that is factory correct on very few cars for the 1970 model year. I will pull that letter and certification and repost later quoting directly from Al to explain this occurrence. My Vin # and this cars Vin # are close together.

I will be back shortly.
wow....that's pretty cool that it was a known and documented anomaly. I have no skin in the game, but am very interested in hearing it
Old 08-05-2013, 08:54 PM
  #14  
7T1vette
Team Owner
 
7T1vette's Avatar
 
Member Since: Jan 2006
Location: Crossville TN
Posts: 36,600
Received 2,715 Likes on 2,273 Posts

Default

The word processor is humming away as we speak...


[just kidding ; I'm interested in seeing the documentation, too. ]
Old 08-05-2013, 10:00 PM
  #15  
Vetterbegood
Advanced
Thread Starter
 
Vetterbegood's Avatar
 
Member Since: Jun 2011
Location: Louisville KY
Posts: 61
Received 1 Like on 1 Post

Default

Originally Posted by deejaydu
Let me help to clear things up. I also own a 350/350hp factory A/C with power steering but in a convertible. It also has the reverse "J" stamped on the pad identical to the pictures that have been posted. It also raised a question with me before I bought the car however, my car has an Al Greening certification and a letter from Al Greening with it explaining the whole reverse "J" anomaly that is factory correct on very few cars for the 1970 model year. I will pull that letter and certification and repost later quoting directly from Al to explain this occurrence. My Vin # and this cars Vin # are close together.

I will be back shortly.
Well I'll be damned.... That's an answer I never expected
Thanks !!! What a great resource community this is, we are all lucky !
Old 08-05-2013, 10:23 PM
  #16  
deejaydu
Safety Car
 
deejaydu's Avatar
 
Member Since: Mar 2007
Location: Blairsville , Georgia
Posts: 4,145
Received 480 Likes on 337 Posts

Default Reverse "J" engine verification

Ok guys here we go. As promised I will share some of the most important information from the letter from Al Grennings Company " Classic Car Affirmation Service, LLC".

" The cylinder case casting date, casting number and engine pad have been carefully reviewed. We note that there is an "M sequence number" for a casting date on your cylinder case in place of the normal alpha/numerical application. This aberration , although not at all very common, has been satisfactorily studied and accepted as a legitimate factory practice relating to the tracking of casting patterns. It is completely acceptable as a normal 1970 small block foundry practice.

We also note that the last letter in the assembly suffix code is not a normal character. Instead of "CTJ" which would be normal for 350H.P.,power steering and A/C, the "J" character is a reversed aberration". In combination, the "M" casting date and plainly strange "J" character may certainly cause questioning. However, examples in our objective data base allow us to be completely satisfied as to your car's cylinder case legitimacy in spite of the "M" casting date and aberrant "J"."

I would also like to add that the cars VIN # in this ad is less than 10 cars from my VIN #. It was built just a few cars after mine and probably on the same day as mine in the first week of June 1970.

Seeing this same reverse "J" on the for sale car goes along way to also confirm the content of Al's letter pertaining to my car.

I hope that this helps to clear this very little known about engine suffix aberration up as there may be a few other cars out there like these two.

Jay
Old 08-05-2013, 10:39 PM
  #17  
whitehause
Pro
 
whitehause's Avatar
 
Member Since: Jun 2009
Location: Fleetwood PA
Posts: 613
Likes: 0
Received 3 Likes on 3 Posts

Default

pretty cool, thanks for sharing that !

Get notified of new replies

To 1970 engine block pad stamp question

Old 08-05-2013, 11:17 PM
  #18  
Mike Ward
Race Director
 
Mike Ward's Avatar
 
Member Since: Jul 2001
Posts: 15,892
Likes: 0
Received 30 Likes on 28 Posts

Default

Originally Posted by deejaydu
I would also like to add that the cars VIN # in this ad is less than 10 cars from my VIN #. It was built just a few cars after mine and probably on the same day as mine in the first week of June 1970.
Although this doesn't explain HOW it happened, it seems obvious with the existence of two known cars that it did.

Is your engine assembly date (0509) that same as the OP's?
Old 08-05-2013, 11:29 PM
  #19  
deejaydu
Safety Car
 
deejaydu's Avatar
 
Member Since: Mar 2007
Location: Blairsville , Georgia
Posts: 4,145
Received 480 Likes on 337 Posts

Default

Originally Posted by Mike Ward
Although this doesn't explain HOW it happened, it seems obvious with the existence of two known cars that it did.

Is your engine assembly date (0509) that same as the OP's?
Mike I will have to check because I do not know for sure but I do know that both cars were built on the same day with the Vin's single digits apart. His car is built just a few after mine.

Jay
Old 08-06-2013, 07:04 AM
  #20  
Alan 71
Team Owner
 
Alan 71's Avatar
 
Member Since: Sep 2006
Location: Westminster Maryland
Posts: 30,173
Likes: 0
Received 2,878 Likes on 2,515 Posts

Default

Hi,
This is certainly interesting reading.
It leads one to believe that very few people should be commenting on stamp pads since we see so few.
No more for me!
Regards,
Alan


Quick Reply: 1970 engine block pad stamp question



All times are GMT -4. The time now is 04:08 PM.