Numbers Matching?
Le Mans Master
Joined: Feb 2001
Posts: 6,317
Likes: 291
From: Ocala FL
Matching numbers is easy. You go down to Sears or TruValue, buy a set fo stamps, and then stamp your numbers in.
They match.
It will be ridiculed beyond belief when someone posts it on here, though.
Like Mike said, "matching numbers" is a term that needs to disappear. http://www.webcitation.org/query?url...10-25+09:12:33
Alan mentioned the decking. There are several ways to handle this.
Broach markings were the lines cut unintentionally longitudinally in the block as they were dragged under the broach that cut the deck. JohnZ has a great picture of an engine broach somewhere. They didn't machine each one like in a machine shop.
As the broach cut across, it would cut nearly no lines when new and as the broach edge wore, it would get rough and cut random lines in the deck.
1. Find an unstamped block from that time period and start with a blank pad. This will have correct broach markings and as long as the stamps are done very well, it will be nearly impossible to judge wrong. However, the broach markings changed from line to line and from day to day, so you need to be right on top of the correct date, or comparison to the photo library of engine stamp pads will show how the block doesn't match the dates. However, there is leeway, as the broach WILL be correct (it is original) for the casting date, and as long as the assembly date is within reason, there is no way to disprove. However, you can't expect a casting day of Feb 5 to have been assembled on April 7. Assembly was often the same day and rarely more than a couple of days away.
2. Get a block of the right casting date, then deck the block in a machine shop and mark the pad to look unstamped with fake broach marks. Then stamp correctly again. Same issue as above with the broach marks. These can be found when comparing with the photo library.
Normally the decking machine in a shop cuts with a circular cutter so you see circular swirl marks in the metal. These are obviously wrong and anyone can tell. If they have a fresh cutter
They match.
It will be ridiculed beyond belief when someone posts it on here, though.
Like Mike said, "matching numbers" is a term that needs to disappear. http://www.webcitation.org/query?url...10-25+09:12:33
Alan mentioned the decking. There are several ways to handle this.
Broach markings were the lines cut unintentionally longitudinally in the block as they were dragged under the broach that cut the deck. JohnZ has a great picture of an engine broach somewhere. They didn't machine each one like in a machine shop.
As the broach cut across, it would cut nearly no lines when new and as the broach edge wore, it would get rough and cut random lines in the deck.
1. Find an unstamped block from that time period and start with a blank pad. This will have correct broach markings and as long as the stamps are done very well, it will be nearly impossible to judge wrong. However, the broach markings changed from line to line and from day to day, so you need to be right on top of the correct date, or comparison to the photo library of engine stamp pads will show how the block doesn't match the dates. However, there is leeway, as the broach WILL be correct (it is original) for the casting date, and as long as the assembly date is within reason, there is no way to disprove. However, you can't expect a casting day of Feb 5 to have been assembled on April 7. Assembly was often the same day and rarely more than a couple of days away.
2. Get a block of the right casting date, then deck the block in a machine shop and mark the pad to look unstamped with fake broach marks. Then stamp correctly again. Same issue as above with the broach marks. These can be found when comparing with the photo library.
Normally the decking machine in a shop cuts with a circular cutter so you see circular swirl marks in the metal. These are obviously wrong and anyone can tell. If they have a fresh cutter
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
It used to mean 'the original born-with factory engine'- at a bare minimum. Now it can mean that the number the buyer offers matches the number the seller will accept.
Melting Slicks
Joined: Aug 2012
Posts: 3,487
Likes: 83
From: Titusville Florida
Because if you ask 10 people you'll get 15 definitions, each of which gets viciously defended to the death as the being the 'official' meaning.
It used to mean 'the original born-with factory engine'- at a bare minimum. Now it can mean that the number the buyer offers matches the number the seller will accept.
It used to mean 'the original born-with factory engine'- at a bare minimum. Now it can mean that the number the buyer offers matches the number the seller will accept.
Le Mans Master
Joined: Feb 2001
Posts: 6,317
Likes: 291
From: Ocala FL
The reason many of us hate this term is that used car salesmen use it to infer the car is original when it legally isn't. So they sell the car at an original price to a newbie, and then they come here moaning how they just overpaid by thousands for a car that is not the original engine. The buyer can't sue in court and win because legally it is "matching numbers" but it isn't original, which the buyer assumed by the terminology.
I know there is the old "Let the buyer beware", but if we as a hobby keep "matching numbers" in use, then we help the used car salesman rip off the newb.
Personally, I have more morals and ethics than to do that.
All "matching numbers" means is the numbers match. I could have stamped them in today and they would match.
Melting Slicks
Joined: Aug 2012
Posts: 3,487
Likes: 83
From: Titusville Florida
sounds like the newbs just need to educate them self, you can't blame the term for what the crook is doing...
If my car is truly numbers matching I'm going to say it is, because it is...
If my car is truly numbers matching I'm going to say it is, because it is...
Safety Car
Joined: Sep 2011
Posts: 4,117
Likes: 1,230
From: Madeira Beach, FL
2024 C8 of the Year Finalist - Unmodified
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2020 C3 of the Year Finalist - Unmodified
TheBlackVette,
Thankyou for the nice comment regarding my post.
This Forum is great because we have Vanilla, Chocolate, & Strawberry
as choices.
There are contributors that have such good documentation....ie Allan,
that if you need tech support or pictorial tutorials he has it. ( I think they are words)
There are engine builders and racers etc.... if you want to build a 6,000
RPM big block just ask.
There are engineers and scientist here if you want a 4 hour read on oil properties.
There are critics if you want sarcasim.
And lastly there are average Joe's like me just glad to have a vette.
It took 50 years but it's finally a reality.
Over all we have a good group.
Oh and don't let me forget Lars as where else could one go this day and age and have real time real world GM know how about quadrajets
since they haven't been in service since 1984.
I've learned a boat load of info about my car from this forum.
Hope to be wiser after four years and start giving back.
I think unless you are an original owner of your vette such as Alan, it is impossible without speaking with each individual previous owner about whats been done to the car you presently own.
I had a 1973 Duster 340, 4speed car in high school that I buggered pretty good street racing around Philly, PA in 1978-80 era.
Today that car is sitting somewhere and some Mopar lover is going why did someone do that?
It was no big deal in the era just another used car made to go fast.
I think with the corvettes they experienced similar fate from PO as well.
Now we sit back and are the ones saying what were they thinking when they screwed on these fender flares
It is what it is.
Marshal
Thankyou for the nice comment regarding my post.
This Forum is great because we have Vanilla, Chocolate, & Strawberry
as choices.
There are contributors that have such good documentation....ie Allan,
that if you need tech support or pictorial tutorials he has it. ( I think they are words)
There are engine builders and racers etc.... if you want to build a 6,000
RPM big block just ask.
There are engineers and scientist here if you want a 4 hour read on oil properties.
There are critics if you want sarcasim.
And lastly there are average Joe's like me just glad to have a vette.
It took 50 years but it's finally a reality.
Over all we have a good group.
Oh and don't let me forget Lars as where else could one go this day and age and have real time real world GM know how about quadrajets
since they haven't been in service since 1984.
I've learned a boat load of info about my car from this forum.
Hope to be wiser after four years and start giving back.
I think unless you are an original owner of your vette such as Alan, it is impossible without speaking with each individual previous owner about whats been done to the car you presently own.
I had a 1973 Duster 340, 4speed car in high school that I buggered pretty good street racing around Philly, PA in 1978-80 era.
Today that car is sitting somewhere and some Mopar lover is going why did someone do that?
It was no big deal in the era just another used car made to go fast.
I think with the corvettes they experienced similar fate from PO as well.
Now we sit back and are the ones saying what were they thinking when they screwed on these fender flares
It is what it is.
Marshal
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Melting Slicks
Joined: Aug 2012
Posts: 3,487
Likes: 83
From: Titusville Florida
Safety Car
Joined: Nov 2003
Posts: 4,274
Likes: 6
From: Corvetteville USA
I found out recently someone put a Mexican banana in my ignition coil!
Thread Starter
Pro
Joined: May 2007
Posts: 675
Likes: 1
From: Mount Laurel NJ
Haven't checked internals of engine, but the parts I can tell are from the original 72.
Thread Starter
Pro
Joined: May 2007
Posts: 675
Likes: 1
From: Mount Laurel NJ
72c3vette,
I hope I can offer some positive advise here as this topic comes up often with new aquisitions. I asked this same ? here around 2010 when I became a vette owner too.
My '68 BB was decked and had a head job sometime in the 80's by a previous owner. The orig. passenger side head is the right date code and casting number ending in 215.
Either the machine shop screwed up the other head or hence the reason for the rebuild as it has an early '69 casting number ending 063head on the drivers side. NFI????
I discovered this when I did valve seals winter 2012.
I too thought I bought a car that maybe ruined value wise.
Again, after some forum feedback and considering what I wanted to do with the car the issue became less and less important.
I still get all the wow factor w/o being asked to open my hood so they can check the vin pad.
Mr car has 81,000 orig. miles now and many orig. survivor parts which I find neat. Just because this motor was freshened up in the 80's doesn't detract from the fact it is still a cool vette.
It actually saved me about 4 grand.
This whole NCRS judging came about in like 1979-1980ish.
Men like MF Dobbins took the corvette to another level with the document process, did it sell allot of his books... yeah it did.
I have two of them they are not cheap. Also sold allot of authenic replacement stickers too. Men made $$$$ off the process and still do.
You can enjoy it as it is as I do or take it to the next level, your choice.
I'd like to get mine judged someday even if it takes 2nd flight.
I'm not going to throw a zillion dollars at it to make some judging staff warm and fuzzy.
Before that any car rebuilt with a NOM or having the orig block deck surfaced was a plus it meant you had a new or fresh power plant.
Before all this judging stuff these cars were cruising toys like in Happy Days. Everybody met up at Mel's and had a cool time.
People would dig the car for what it was not what it wasn't.
If you went about restoration even with a NOM you would take a deduction at judging time but who says you can't try it and have fun experiencing the process.
Hope this helped
Marshal
I hope I can offer some positive advise here as this topic comes up often with new aquisitions. I asked this same ? here around 2010 when I became a vette owner too.
My '68 BB was decked and had a head job sometime in the 80's by a previous owner. The orig. passenger side head is the right date code and casting number ending in 215.
Either the machine shop screwed up the other head or hence the reason for the rebuild as it has an early '69 casting number ending 063head on the drivers side. NFI????
I discovered this when I did valve seals winter 2012.
I too thought I bought a car that maybe ruined value wise.
Again, after some forum feedback and considering what I wanted to do with the car the issue became less and less important.
I still get all the wow factor w/o being asked to open my hood so they can check the vin pad.
Mr car has 81,000 orig. miles now and many orig. survivor parts which I find neat. Just because this motor was freshened up in the 80's doesn't detract from the fact it is still a cool vette.
It actually saved me about 4 grand.
This whole NCRS judging came about in like 1979-1980ish.
Men like MF Dobbins took the corvette to another level with the document process, did it sell allot of his books... yeah it did.
I have two of them they are not cheap. Also sold allot of authenic replacement stickers too. Men made $$$$ off the process and still do.
You can enjoy it as it is as I do or take it to the next level, your choice.
I'd like to get mine judged someday even if it takes 2nd flight.
I'm not going to throw a zillion dollars at it to make some judging staff warm and fuzzy.
Before that any car rebuilt with a NOM or having the orig block deck surfaced was a plus it meant you had a new or fresh power plant.
Before all this judging stuff these cars were cruising toys like in Happy Days. Everybody met up at Mel's and had a cool time.
People would dig the car for what it was not what it wasn't.
If you went about restoration even with a NOM you would take a deduction at judging time but who says you can't try it and have fun experiencing the process.
Hope this helped
Marshal
I'd love to find my original block, however I'm not going to go crazy as the car is more for my enjoyment by driving it and fixing it up than NCRS.
Safety Car
Joined: Nov 2003
Posts: 4,274
Likes: 6
From: Corvetteville USA
Yep I NEVER heard "numbers matching" in Kissimee when I was there. Not once, ever....
Spectators did ask about if I had correct parts to the car and when I said please take a look they were happy to do so. First thing that the overwhelming majority said is my alternator was not correct.
That damn alternator gave me grief.
Never thought about that until now.
Spectators did ask about if I had correct parts to the car and when I said please take a look they were happy to do so. First thing that the overwhelming majority said is my alternator was not correct.
That damn alternator gave me grief.
Never thought about that until now.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
NCRS does not look at the transmission stamp.
NCRS does not establish/authenticate whether the engine is the 'original born with' or not.
Melting Slicks
Joined: Aug 2012
Posts: 3,487
Likes: 83
From: Titusville Florida
yeah it would be kinda hard to get to the VIN on tranny.
If they don't look for establish if the engine was born with the car then why are folks saying you will get deductions? I could personally care less about NCRS judging, I've changed enough on mine (but have kept the parts), that it will not do well in NCRS judging anyway.
Melting Slicks
Joined: Nov 2004
Posts: 2,672
Likes: 6
From: Nevada City California
The best type of scrutiny by the NCRS judges is Bowtie judging. They go over the entire car the way it ought to be for evaluating whether such candidate is representative of the way these Corvettes left the factory.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
If they don't look for establish if the engine was born with the car then why are folks saying you will get deductions? I could personally care less about NCRS judging, I've changed enough on mine (but have kept the parts), that it will not do well in NCRS judging anyway.
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
My understanding is 'Bowtie' judging is based on having few if any replacement parts, a survivor. Flight judging focuses on 'correct' parts as built in the day, allows for replacements or restorations. I don't see either as being wrong, different judging criteria.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
NCRS - CHEVROLET BOWTIE Award
This award was created by the National Corvette Restorers Society in 1992. The Bowtie award recognizes the un-restored Corvette and encourages the owner to retain and display the car in its present condition for the enjoyment and continuing educational benefit of our membership. The award is earned only at a National Convention by un-restored cars successfully judged and voted to be historically and educationally significant in four areas (Interior, Exterior, Mechanical and Chassis). This award is available to any model year currently judged by NCRS which was manufactured 20 or more years ago. Regardless of change in ownership or judging result the car may never be presented for judging again. The judged section requires an 80 to 85% pass with the following standard "Does the item, part, fabric, plating or coating appear to actually be that which was specifically installed or applied on this car at the time of manufacture". If this is successfully passed the vote with the following standard "Does the area judged display significant educational and historical value which should be preserved in its present condition" is taken. Passing both sections in all four areas earns the NCRS - Chevrolet Bowtie award. Only 277 Corvettes have received this prestigious award.