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Numbers Matching

Joined
Jun 13, 2010
Messages
234
Location
Surprise, AZ
Corvette
87 Callaway Cpe 87-070 & 68 Cpe 427, 4spd A/C
It seems on the older cars that just about everything has a "Number" "Date Code" or some other relivent info on parts of our beloved corvette's. :ugh

So what constitues "Numbers Matching" & just how many items on the cars are marked? Once I start digging through this car where is a good place online to verify all these numbers. Thanks for the help.

i10fwy
 
The term matching numbers has been abused into virtual uselessness as no two people seem to agree on it's exact definition. It used to mean 'the original engine that GM installed on the production line', now it can mean 'a replacement engine that was restamped to look like the original'. There's dozens of parts on a car that have a part number and date code on them but only the engine block, transmission main case and frame had the VIN derivative stamped into them.

You don't hear 'real car guys' use the term very much.
 
The term matching numbers has been abused into virtual uselessness as no two people seem to agree on it's exact definition. It used to mean 'the original engine that GM installed on the production line', now it can mean 'a replacement engine that was restamped to look like the original'. There's dozens of parts on a car that have a part number and date code on them but only the engine block, transmission main case and frame had the VIN derivative stamped into them.

You don't hear 'real car guys' use the term very much.

Yeah I know, I find it odd that NCRS considers restamping a correct but not original to the car engine ok in their eyes. Wouldn't one think that only the born with engine would have the pad stamped? I haven't dug into this car yet but the prior owners statement is that it is 100% with exception of the block. Stating it was blown up shortly after new. But I don't recall seeing a CE. I guess I will have to dig out the NCRS books.

i10fwy
 
Yeah I know, I find it odd that NCRS considers restamping a correct but not original to the car engine ok in their eyes.

They don't. A restamped engine (that gets detected) gets a full deduct of all points allocated, not that there's many points allocated in the first place. There's also no attempt during judging to determine if the engine (or any component) is the original or is 'authentic', nor issue any certification to that effect.

Common misunderstanding.;)
 
They don't. A restamped engine (that gets detected) gets a full deduct of all points allocated, not that there's many points allocated in the first place. There's also no attempt during judging to determine if the engine (or any component) is the original or is 'authentic', nor issue any certification to that effect.

Common misunderstanding.;)

Don't know where you get your info Mikey. Im have in front of me NCRS JUDGING - OWNERS ADVISORY just sent to me this week

Definitions of Counterfeit vs Restoration

"NCRS does not consider the restoration or replacement of components as counterfeit as long as the intent is to restore the car to it's former or original state as it left the factory. To make this perfectly clear, read the following definitions from Webster's dictionary and the accompanying examples."

Restore: "to renew" to put back into existence or bring back to a former or original state"

Bullet Point #3

"Stamping a 435 HP block to conform to the date/serial number of the original 435 HP Corvette in which it is to be installed."

So the way i read it is, If it was a 427/400 to begin with it's ok to put a restamped one in!

i10fwy
 
If I were you,I would call the National NCRS in Cincinnati,and ask them about your engine,
in a "hypothetical situation' and see what they say.The past year,they have blacklisted several corvettes
for 're stamped' engines and vin tags.
especially if you plan on getting your corvette flight judged.
 
Don't know where you get your info Mikey. Im have in front of me NCRS JUDGING - OWNERS ADVISORY just sent to me this week

Definitions of Counterfeit vs Restoration

"NCRS does not consider the restoration or replacement of components as counterfeit as long as the intent is to restore the car to it's former or original state as it left the factory. To make this perfectly clear, read the following definitions from Webster's dictionary and the accompanying examples."

Restore: "to renew" to put back into existence or bring back to a former or original state"

Bullet Point #3

"Stamping a 435 HP block to conform to the date/serial number of the original 435 HP Corvette in which it is to be installed."

So the way i read it is, If it was a 427/400 to begin with it's ok to put a restamped one in!

i10fwy

What you're reading is the NCRS definition of restoration vs. counterfeit. If something is restored but incorrectly (like an engine stamp pad) then it gets a deduct. That's what the judging is for- seeing how well a car has been restored or preserved. If a pad has been restored so accurately and undetectably that the judges cannot tell the difference- then how would they know it's a restamp? There is no allowance or exceptions to just 'let slide' restamps that are detected. The three engine pad features that are judged are each all-or-nothing deducts.

The past year,they have blacklisted several corvettes
for 're stamped' engines and vin tags.

Sorry Bill, that's incorrect and misleading. There is no rule about blacklisting restamped engines. A bogus VIN tag will cause the car not to be judged at all as will a reproduction trim tag on a C2. Those two things are essentially the first things that get checked. A car configured with options that it did not have when born will carry a penalty from event to event until such time as it is restored to original config. Owners that consistently try to pass off bogus cars face the possibility of getting the boot.

The OP can call head office if he wants to confirm this, but there's plenty of judges that hang our here on CAC.
 
I don't disagree, I find it quite odd that NCRS would word it like that. There is a regional coming up next month, I plan to attend. For the purpose of gaining knowledge. I have applied to be a observer judge and would also like to attend judges school. I would think it would make more sense to leave the pad blank. It could be a totally correct engine, but restamping IMHO is misleading even if it is for "restoration" purposes.


i10fwy
 
Attending a meet is an
Excellent way to find out what you need to know..
 
...If I were you,I would call the National NCRS in Cincinnati,and ask them about your engine,...

No real need to call the NCRS, Bill. He already knows the block is a replacement.

i10: dig out your NCRS books and read up. All the various numbers you want to look for will be listed. Most people are happy if the VIN derivitive stamps on the block and transmission match the VIN on the car. If you know the block has been replaced, no real need to look for the VIN derivitive on it.

:D
 
I don't disagree, I find it quite odd that NCRS would word it like that. There is a regional coming up next month, I plan to attend. For the purpose of gaining knowledge. I have applied to be a observer judge and would also like to attend judges school. I would think it would make more sense to leave the pad blank. It could be a totally correct engine, but restamping IMHO is misleading even if it is for "restoration" purposes.


i10fwy

The reason the NCRS clarified their position is well known- the engine is to be treated no differently than any other component of the car. Restoring is restoring whether it be body panels, paint, seat covers, engine pads, whatever. The key is putting back something to a condition that was once there. As per your quote: "Stamping a 435 HP block to conform to the date/serial number of the original 435 HP Corvette in which it is to be installed." If the block was never a 435 block to start with (say it was a 'wimpy' 390 :D) how can it be restored to a 435 block?

I do agree with you about restamping for judging purposes- the amount of points available does not justify the expense and ensuing controversy when the subject of 'factory original' or 'matching numbers' :ugh comes up . It is a shame that so many owners use the judging awards for personal gain and choose to perpetuate the myth that an award certifies that a car is original and authentic. This subject is one of my favourite rants on another discussion board I belong to.
 
That's why the engine block is the only item on the car that's judged in a defined, sequential manner, with a "go" or "no go" at each step, and the stamp pad is last, with minor deductions compared to the first two steps:

1. The block casting number is judged first - if it's not correct, block judging stops and a 350-point deduction is taken. If it's correct, judging proceeds to the block casting date.

2. The block casting date is judged second - if it's not within six months of the car's final assembly date, block judging stops and a 175-point deduction is taken. If it fits in the window, judging proceeds to the stamp pad.

3. The block pad stampings and pad surface are judged last - if either the engine plant stamp or the assembly plant VIN derivative stamping aren't correct, each gets a 25-point deduction. The pad surface is judged, and if not deemed typical, it gets a 38-point deduction.

NCRS Flight Judging is based on the APPEARANCE of originality as defined by the published judging standard, not that any item IS ORIGINAL to the car. Absolute originality ("born with" parts) is handled in Star/Bowtie judging, which is an entirely different process, only done once a year at the National Convention; that category is FAR more demanding than the "Survivor" judging done at Bloomington Gold - you can't "build" or "create" a Star/Bowtie car.

:beer
 
John, Thank you! A real explanation that makes sense. :happyanim: So if my car has a correct engine, casting is proper & and date is accurate but the pad is inaccurate the deduction is minimal? So is it better then to leave the pad as is or blank?

Chris
 
As noted above- the pad deduction is minimal as compared to other features of the car

25 points for the engine code
25 for the VIN derivative
38 for the pad surface

Each is judged individually but each is an 'all or nothing' decision, no partial deducts on any one feature. If your pad still has a typical factory surface finish, typically called 'broach marks' best leave them as-is in order to get those 38 points. There's no need or benefit in removing the other information


For reference, a burnt out tail light or non-functioning cigar lighter is each a 25 point deduct

Edit- the Bowtie/Star event that John mentioned above is exclusively for unrestored cars- any signs that it's been restored, massaged or even taken apart extensively (such as engine overhaul) will usually cause it not to be given a pass mark in that category. Very, very difficult award to win.
 
What are the stampings on your pad?
:thumb

Mike, we are now calling this car Waldo, it is still not here. Two weeks on a transport crossing the southern US everyday we go online "where's Waldo?" When it gets here then I can start diggin through it. Paperwork "docs" are on the way too from NC.

i10fwy
 

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