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Help decoding numbers stamped on the block- added picture
On the block pad is the number 19S700792. This decodes as a 1969 Chevy Corvette block, for a car built in the St Louis plant, sequence no. 00792.
The two digit suffix is HW which is for 350HP 4 speed.
Also on the block pad is the number 74156. I can't find any information that would tell me what this number represents. Does anyone know?
Thanks for your help. 74156 is beneath the block stamp serial number
I hope you guys can see this. I am new to editing on the Corvette Forum and the image is large, but I can scroll up and down and see the number beneath the block serial number. Thanks for your help.
Last edited by Mrt69vette; Apr 23, 2026 at 09:41 AM.
Reason: Add a picture of the block pad stamping
On the block pad is the number 19S700792. This decodes as a 1969 Chevy Corvette block, for a car built in the St Louis plant, sequence no. 00792.
The two digit suffix is HW which is for 350HP 4 speed.
Also on the block pad is the number 74156. I can't find any information that would tell me what this number represents. Does anyone know?
Thanks for your help.
A photo would help a lot.
Is the 74156 just before the HW? If so I'd say it's the engine plant and date but is either being misread, has degraded, or has been over-stamped during a rebuild for some reason. Engine plant stamp should be VxxxxHW.
On the 1969 SB L46 (350/350) the partial VIN is stamped on the left side of the pad. The right side should have the letter “V” for Flint followed by the engine assembly date and engine code. In your case the L46 with no AC code is “HW”. Those should be the only things stamped on the pad.
The left and right sequence is reversed for BB cars.
The numbers you are asking about, if you are reading them correctly, should not be on the pad unless they were stamped at some point later.
Raised casting numbers are in a totally different place.
As others have mentioned a picture would be very helpful .
Hope that helps. Take care!
Last edited by avalonjohn; Apr 22, 2026 at 02:48 PM.
This is the factory engine for the car. I have only owned it a couple years, and don't know if that could be a machine shop stamp. I added a picture. Thanks
This is the factory engine for the car. I have only owned it a couple years, and don't know if that could be a machine shop stamp. I added a picture. Thanks
Can you take a photo that shows the upper end of the pad where the HW is visible?
This is the factory engine for the car. I have only owned it a couple years, and don't know if that could be a machine shop stamp. I added a picture. Thanks
I'm not sure how you can state that when the evidence does not make that clear. If the partial VIN is correct, the other stamp was added later. Isn't it just as likely that the VIN stamp was added later?
Thanks for the photo! If it were my car, I'd get some brake fluid or acetone and very CAREFULLY remove the paint from the engine stamp pad. Read some other threads on how to do this. Abrasives will destroy evidence (if that hasn't been done already). What you are looking for is likely to be on the other side of the pad (the top part of your image, partially cropped out).
Do you have any documentation for the car (build sheet, perhaps), that confirms the HW (L46) engine assumption?
Last edited by Bikespace; Apr 23, 2026 at 10:00 AM.
The character shapes actually look good to my eye, but it certainly isn't in the correct spot for a factory stamp. Those guys were stamping many hundreds of blocks every day, so were pretty consistent with placement (would have been done before the VIN was placed). Wouldn't be a CE block because they wouldn't get VIN stamps at the dealerships.
Help decoding numbers stamped on the block- added picture
