DZ stamp

[67 kemie ss]

Stamp or re-stamp?  

Thanks

[z28z11]

Difficult to tell for sure - stamping appears correct, but the block surface looks a little weird. No real obvious evidence of broaching lines - surface almost looks shot peened, or blasted, but it could be O.K. I don't think the Van Nuys VIN stampings ever made it to the block side as did Norwood's above-the-filter stampings, so at least that matches.

Without a larger view of the deck surface, it would be difficult to pronounce a verdict one way or the other. At least no decking lines visible -

Regards

[1968RSZ28]

I saw that block on eBay, I was going to post in the Orphans section, but no partial VIN is listed...

http://www.ebay.com/itm/DZ-302-Engine-Block-Crank-1969-Camaro-Real-Barn-Find-1967-1968-/231253860005?pt=Motors_Car_Truck_Parts_Accessories&hash=item35d7cddea5&vxp=mtr

Paul

[69Z28-RS]

Due to the fact that the stamp appears OK, and the deck surface around it appears 'aged/old'..  doesn't appear to have been machined any time recently...  I'd lean towards it being correct...   if all other indicators were good re the engine...

[firstgenaddict]

The double tap on the Z also leads me to believe it is real.
I read a metallurgical engineer's statement recently that using a thermal imaging camera on a tripod, start the engine, allow to come to operating temp, then cut it off, take a pic of the pad every 15 minutes and the original stamp will appear. Said that you couldn't grind away enough of the pad to get rid of it and still have the block useable. I'd like to see if this works... anyone have a TI camera?

[cook_dw]

I have a thermal imaging camera that I use at work.. I actually was using it this morning.  Its a Fluke Ti32.    Hmmm..  They only cost about $8K

[cook_dw]

I have a decked bbc at home.  Ill take the "tic" home and see if the numbers show up when I apply heat from a propane torch.  Should be a good test.

[cook_dw]

Ok I have attempted the TIC trick and I see nothing.  Maybe I am not getting it hot enough before letting it cool.  I should have grabbed the tripod but forgot it at work.  Also this is a bare block and it may need the entire engine brought to temp.  IDK  I plan on trying again later on when the temps in the garage drop below 90...

[firstgenaddict]

Blue is coolest I expect, if so then there is no deep radiating heat and the pad itself is not 100 deg, correct?
I think there are faints of some characters the way it was described to me was the engine needed to be brought up to temp then the pic every 10 or 15 min through cool down. The heat cycle will be completely different and hold longer vs heating the pad directly, maybe a rosebud on an oxyacetylene torch working in large circles under the pad.
If you had a industrial parts washer for cleaning engine parts it may work since the block is completely heated, hell leaving it outside one afternoon around here would get it 120.

[cook_dw]

On the right you will see the color scales vs temp.  Black and then purple is the coolest.  This scale will change once it sees temps above or below its calculated range and will recal for that.  I tried this again later on last night and got the pad extremely warm (around 200*F) and I allowed it to cool and took a few shots of it and still could not see anything materializing.  I need to try this with an engine that is running and use the tripod and do the 15 min photo cycles.  I believe it will work I just need to nail down the process.

[Mike S]

 I have seen people try this method before and never once seen it work.
I suspect a lot has to do with the original impact of the characters and the depth of the milling.

Mike

[KurtS]

Restamp.

[firstgenaddict]

I have seen people try this method before and never once seen it work.
I suspect a lot has to do with the original impact of the characters and the depth of the milling.

Mike

Take this with a grain of salt as I haven't ever seen it done, however the engineer stated that "you couldn't grind enough metal away to get rid it without ruining the block".