block restamping










On the other hand, why is only the engine so important when much of the rest of a Bloomington Gold car could be replacement parts??
If someone like me, with a real L71 engined car, blew an engine, he would be taking $50,000+ hit on the value of the car. Sure would be tempting to spend a few thousand $$$ to duplicate that block.

Of course to many people they don't care at all. It depends on how you were taught to evaluate and care for your cars. Not saying this is right or wrong way to evaluate, or even if it is significant. It is to some so in my opinion restamping is a deception.






Last edited by kenba; Jul 31, 2016 at 11:04 AM.






Of course to many people they don't care at all. It depends on how you were taught to evaluate and care for your cars. Not saying this is right or wrong way to evaluate, or even if it is significant. It is to some so in my opinion restamping is a deception.






Would you want to spend the rest of your days in court helping one guy sue the other?
And I would have to disagree with you about "less to do with the numbers" part of your statement.
The analysis is about brooch mark and pad stamp, both as a function of time frame.
Let me provide an example:
Lets say a 67 435 engine is with an engine stamp of T04I2JE is submitted for evaluation.
Now, lets also say that there are 5 known (believed to be, anyway) original examples of JE engines assembled on 04I2 (April 12th). NOw lets also say that the top curve of the digit '2' is weak / lightly stamped relative to the rest of the characters (perhaps because of wear on the '2' digit stamp).
We would expect the submitted example to also show this weak top curve of the digit 2.
OK, this is a very simplistic answer to a rather complex process that examines the pad, the brooch marks, the edge of the pad, the style of the characters that are stamped, the uniformity of the characters, the depth of the characters, the position of the characters on the pad,.... the list goes on.
I do not recall Al Grenning's process using anything like a comparison microscope, which is the tool typically used in bullet comparisons. And the matching of brooch marks to a specific point in time is somewhat inaccurate. It is a data point, one of many that are used in the process.
The examples I cited earlier would all pass muster, because the brooch marks WERE original, as was the engine stamp. Taking a 230hp 57 283 out of a Corvette, and replacing it with a closely dated 283hp 283, also a Corvette engine, is very difficult to detect.
The point I am making is that, when Al provides a affirmation, he provides a letter that he signs stating that in his opinion, and based on his available comparison data, the engine is correct. What he doesn't provide are actual examples of the engine pad stamps that were used to make this determination.
And the presence or absence of that actual evidence is what makes the difference between his affirmation (i.e. his opinion), and tangible evidence that can be pointed to as specific data.
When I was judging at NCRS meets, and I called for a deduction on something, I had to be able to point to / describe something specific that differed from "typical of factory production". What is missing from the engine affirmation service is the "something specific".
I get why he does not provide this, but without those comparison photos, it is just a letter, backed by the faith that his placed in the letter.
Now, let me be clear on this point, I am NOT making any sort of negative or questionable comments about Al Grenning or his affirmation service. I have no reason to believe that Al Grenning has anything but the best interest of the hobby at heart when he does his evaluations.
Here is a link to Al Grenning's patent application, which is now expired. Interesting reading.
https://www.google.com/url?sa=t&rct=...KZUCfabVzKtubQ
Last edited by emccomas; Jul 31, 2016 at 02:03 PM.
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And the presence or absence of that actual evidence is what makes the difference between his affirmation (i.e. his opinion), and tangible evidence that can be pointed to as specific data.
When I was judging at NCRS meets, and I called for a deduction on something, I had to be able to point to / describe something specific that differed from "typical of factory production". What is missing from the engine affirmation service is the "something specific".
I get why he does not provide this, but without those comparison photos, it is just a letter, backed by the faith that his placed in the letter.
His "something specific" is his opinion that the broach marks and stampings don't look like the ones he's seen that he's convinced are real. You are right... it's just a letter.
I've had some experience with collectible autographs and verification of sports memorabilia. No one is willing to risk being sued anymore, so everyone just says "this is my opinion," whether in person or in writing. But nobody offers comparative photgraphy of their files of similar autographs as support. It's an opinion, based on their experience and knowledge base, and you can do with it what you like.
Unless Al is willing to come off the "opinion" part of it in a courtroom, I don't expect a file of supporting documentation to support his opinion.
His "something specific" is his opinion that the broach marks and stampings don't look like the ones he's seen that he's convinced are real. You are right... it's just a letter.
I've had some experience with collectible autographs and verification of sports memorabilia. No one is willing to risk being sued anymore, so everyone just says "this is my opinion," whether in person or in writing. But nobody offers comparative photgraphy of their files of similar autographs as support. It's an opinion, based on their experience and knowledge base, and you can do with it what you like.
Unless Al is willing to come off the "opinion" part of it in a courtroom, I don't expect a file of supporting documentation to support his opinion.
His "something specific" is his opinion that the broach marks and stampings don't look like the ones he's seen that he's convinced are real. You are right... it's just a letter.
I've had some experience with collectible autographs and verification of sports memorabilia. No one is willing to risk being sued anymore, so everyone just says "this is my opinion," whether in person or in writing. But nobody offers comparative photgraphy of their files of similar autographs as support. It's an opinion, based on their experience and knowledge base, and you can do with it what you like.
Unless Al is willing to come off the "opinion" part of it in a courtroom, I don't expect a file of supporting documentation to support his opinion.
Verne
I suspect the answer would be no, but maybe it is just because no one has asked.
Just to be clear, what I an suggesting is that he send copies of the sample data from his Master Pad Index that he used to make his determination, along with his letter of affirmation.
This is the only way I can think about it.
Last edited by Twan Sloot; Aug 1, 2016 at 03:02 PM.

I suspect the answer would be no, but maybe it is just because no one has asked.
Just to be clear, what I an suggesting is that he send copies of the sample data from his Master Pad Index that he used to make his determination, along with his letter of affirmation.
Last edited by SW Vette; Aug 1, 2016 at 03:17 PM.
However, a number of these engine pads are also posted on the internet. With enough effort, others could put together their own "Master Pad Index", particularly if they were interested in just one engine suffix code.
I suspect the answer would be no, but maybe it is just because no one has asked.
Just to be clear, what I an suggesting is that he send copies of the sample data from his Master Pad Index that he used to make his determination, along with his letter of affirmation.
Fair enough for me .
Al is selling a product - again, that product is his reputation and the voracity of the data he has to back it up. Namely, his database of stamp pads, etc - those are his 'value added' flagship sales products. He won't give it up and neither would I.
And, of course, any expert 'certifier' is going to say they are only expressing their 'opinion'. That's what they are selling. If there was irrefutable, gold-plated, proof that some engine was the original BB that a car was 'born with' you wouldn't need Al's 'opinion'...
As to restamping; its a religious debate with no right answer.
Last edited by Frankie the Fink; Aug 2, 2016 at 09:40 AM.
Last edited by SBR; Aug 2, 2016 at 09:45 AM.












