Real Documentation and Numbers Matching
12-22-2016, 10:37 AM
#41
Melting Slicks
Its a pretty disappointing aspect of the hobby. For those like myself that just want a genuine numbers matching car and genuine factory documentation, i just think that stuff is cool.
I remember learning about the term "numbers matching" and that indicates that the car was original. Following that i learned about "factory documentation" to help prove the car and its options are original to the car. Now i know that "factory documentation is more than likely forged and the "numbers matching" on the cars too being re stamps. I still thought their was hope with broach marks, but from what i have been learning, that seems to be able to be forged as well.
I remember learning about the term "numbers matching" and that indicates that the car was original. Following that i learned about "factory documentation" to help prove the car and its options are original to the car. Now i know that "factory documentation is more than likely forged and the "numbers matching" on the cars too being re stamps. I still thought their was hope with broach marks, but from what i have been learning, that seems to be able to be forged as well.
There are plenty of genuine documented born with drivetrain cars out there for 69. Corvettes, especially 69s are not really that rare. They made lots of cars. It just takes time to look at enough cars and compare to what you know are original cars to start to feel comfortable at what you are looking at. I always see quite a few good cars whenever I check out what's for sale on the Internet.
Hello David Howard,
Great quotes and good advice.
Hello Stan,
I look forward to meeting you in person. Again I missed Carlisle this year. If you are ever out on Long Island please let me know. I would appreciate the opportunity to exchange information.
Happy Holidays,
Ed
03-23-2017, 10:12 PM
#43
Drifting
Your picture is upside down, but date code looks like G 5 8 to me. That would put it cast on July 5th, 1968. That should be correct for an early 69 production car. What is the build date of the car?
03-23-2017, 11:44 PM
#44
Safety Car
The G is a bit hard to read but it couldn't be much else. My 69 BB cast date is the same style with the weird raised cast where the second number for the day if it was double digit would go. My guess is the same. July 5th, 68.
03-23-2017, 11:48 PM
#45
Heel & Toe
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I am trying to understand block casting numbers and casting dates. I've got a couple of pictures of some casting dates.
According to this website below, the 1969 big blocks had an early, mid and late casting number. In what months of production would you expect to see an early, mid or late block in a 1969 Corvette?.
http://corvettec3.ca/casting.htm
03-24-2017, 12:26 AM
#46
Safety Car
No idea about dates when casting designation/placement changes were made. My 69 casting date is not on the side above the oil pan. It's on the back of the block just above the bell housing and below the distributor. Oct 8, 1969 cast date on a 3963512 block. Engine was built Oct 20th in an Oct 24th build car.
03-24-2017, 03:32 AM
#47
CC
Alan Colvin's book Chevrolet by the Numbers is an excellent reference for casting number and dates. He gives approximate dates when the blocks were being cast.
He has the 3935439 block first being used after Jan. 1968. It was used for late 1968s and for very early 1969s.
The mid year 3955270 block only had a very short casting run of Aug. to Oct. 1968.
The 3963512 block began being cast in Oct. 1968 and was used for the rest of the model year. At first the casting date was on the side of the block but was moved to the bell housing flange in late 1969. Colvin has the casting date move as Nov. 1969, but since Grant reports his Oct. car with it in the new location, it must have occurred a little earlier then he states.
John
Alan Colvin's book Chevrolet by the Numbers is an excellent reference for casting number and dates. He gives approximate dates when the blocks were being cast.
He has the 3935439 block first being used after Jan. 1968. It was used for late 1968s and for very early 1969s.
The mid year 3955270 block only had a very short casting run of Aug. to Oct. 1968.
The 3963512 block began being cast in Oct. 1968 and was used for the rest of the model year. At first the casting date was on the side of the block but was moved to the bell housing flange in late 1969. Colvin has the casting date move as Nov. 1969, but since Grant reports his Oct. car with it in the new location, it must have occurred a little earlier then he states.
John
Last edited by JC68; 03-24-2017 at 03:34 AM.
03-24-2017, 07:53 AM
#48
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Hi CC,
When looking at casting numbers and dates on parts that have been painted it's important to not use ANYTHING abrasive, sharp, or hard in an attempt to expose them.
It's wise to use some kind of liquid or gel to remove the paint. That will also help remove the paint in the crevices that make it difficult to differentiate 3s, 6s, 8s and 9s, and also letters like Cs and Gs.
So be careful not to remove any material other than paint at this point.
Regards,
Alan
When looking at casting numbers and dates on parts that have been painted it's important to not use ANYTHING abrasive, sharp, or hard in an attempt to expose them.
It's wise to use some kind of liquid or gel to remove the paint. That will also help remove the paint in the crevices that make it difficult to differentiate 3s, 6s, 8s and 9s, and also letters like Cs and Gs.
So be careful not to remove any material other than paint at this point.
Regards,
Alan
03-24-2017, 09:05 AM
#49
The 3963512 block began being cast in Oct. 1968 and was used for the rest of the model year. At first the casting date was on the side of the block but was moved to the bell housing flange in late 1969. Colvin has the casting date move as Nov. 1969, but since Grant reports his Oct. car with it in the new location, it must have occurred a little earlier then he states.
Colvin is wrong. The move to the bell housing flange occurred at least as early as March 12, 1969.
Dennis
03-24-2017, 10:02 AM
#50
Yeah, he was way off. Looking at a second source, the NCRS judging guide, it says date was moved to flange at approximately SN 20,000. Your car seems to confirm they are correct.
John
03-26-2017, 08:20 AM
#53
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Hi CC,
Judging by the information included in for sale ads I'd have to say WAY over 100%
Regards,
Alan
Judging by the information included in for sale ads I'd have to say WAY over 100%
Regards,
Alan
03-26-2017, 08:26 AM
#54
Team Owner
What do we say in the C2 world? There are more numbers matching BB 65-67 Vettes out there than Chevy ever produced.
03-30-2017, 08:50 AM
#56
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Hi CC,
I REALLY think it's a higher percentage than that.
Are you thinking it's the engine or the documention that drops the percentage so low?
Regards,
Alan
I REALLY think it's a higher percentage than that.
Are you thinking it's the engine or the documention that drops the percentage so low?
Regards,
Alan
Last edited by Alan 71; 03-30-2017 at 08:53 AM.
03-30-2017, 09:25 AM
#57
Melting Slicks
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One more comment on build sheets. When the fuel tank was removed from my car, we found the build sheet. It was 2 pages side by side. It appeared to be pasted to the tank and was very brittle. Some of it literally crumbled in my hand when I tried to pick it up. One side came off relatively easy, but the other had to be removed by cutting the tank.. (The tank was to be replaced anyway) To me it looked like the build sheet must have been some kind of early photo copy paper, because it kind of resembled fax paper. The back of the document was turning black and there were hints of purple on the back of the pages. My car is a 72 I know it was not fake. I know this because I bought the car from the husband of the deceased original owner and they did not concern themselves with such matters. I mainly removed the tank sticker for the purpose of getting a list of the original options. The radio original had been changed and discarded so I needed to know if it was originally a stereo or mono radio. I have some pictures of the build sheet and I will try to remember to post them when I have time.
Last edited by crawfish333; 03-30-2017 at 10:37 AM.
03-30-2017, 10:33 AM
#58
Melting Slicks
My guess would be a higher for real docs and original born with drive train. I am thinking 1 in 4 (25%)
My estimate comes from looking at many 69s and inspecting paperwork from them over the last 30 years. I also have pictures of quite a few tank stickers and engine pads. The one thing that makes the number believably higher with regardbto paperwork is precisely because the tank stickers stayed with the car, provided they didn't deteriorate. Things like window stickers were given to the owners who usually tossed or misplaced them. I know the number of cars with real window stickers is much lower. That could be 10% or less. I have seen far less original window stickers than tank stickers.
If my math is correct (and its a complete guess) then with the large amount of big blocks made in 69 that leaves around 4000 cars that are the real deal. That's quite a few to pick from.
My estimate comes from looking at many 69s and inspecting paperwork from them over the last 30 years. I also have pictures of quite a few tank stickers and engine pads. The one thing that makes the number believably higher with regardbto paperwork is precisely because the tank stickers stayed with the car, provided they didn't deteriorate. Things like window stickers were given to the owners who usually tossed or misplaced them. I know the number of cars with real window stickers is much lower. That could be 10% or less. I have seen far less original window stickers than tank stickers.
If my math is correct (and its a complete guess) then with the large amount of big blocks made in 69 that leaves around 4000 cars that are the real deal. That's quite a few to pick from.
Last edited by ed427vette; 03-30-2017 at 10:35 AM.
03-30-2017, 10:43 AM
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Hi c,
I believe the sheet (s) that ended up being glued to the tank were part of a 7 page 'Corvette Order' form.
I'm unsure if carbon paper was used between each sheet or if the paper was impregnated with carbon to make the copies.
It's some of those additional copies that are occasionally found elsewhere on some cars.
Regards,
Alan
I believe the sheet (s) that ended up being glued to the tank were part of a 7 page 'Corvette Order' form.
I'm unsure if carbon paper was used between each sheet or if the paper was impregnated with carbon to make the copies.
It's some of those additional copies that are occasionally found elsewhere on some cars.
Regards,
Alan
Last edited by Alan 71; 03-30-2017 at 10:47 AM.
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03-30-2017, 11:49 AM
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Note: this thread has been merged with a recent related thread regarding block castings, per OP request. 