Engine Matching Numbers?
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Engine Matching Numbers?
If the head cast date is two days prior to the block cast date, is the engine considered a matching number engine? I have heard that the block cast date should be the same or prior to the head cast date.
68 427/390 HP Engine
Block dated A-10-8
Both Heads Dated A-8-8
68 427/390 HP Engine
Block dated A-10-8
Both Heads Dated A-8-8
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From: Southbound
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... I have heard that the block cast date should be the same or prior to the head cast date...
...Block dated A-10-8...Both Heads Dated A-8-8...
The important thing is that all of the casting dates must precede the engine assembly date stamped on the pad on the block at the front of the right head. The VIN derivitive will also be stamped there.
If your heads were cast on the 8th and your block was cast on the 10th, your engine assembly date must be after the 10th. Occasionally you will see assembly dates the same as a block casting date, but usually not.
If the assembly date stamped on the block is before the 10th, you have trouble since the engine could not have been assembled before the block was cast.
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If the head cast date is two days prior to the block cast date, is the engine considered a matching number engine? I have heard that the block cast date should be the same or prior to the head cast date.
68 427/390 HP Engine
Block dated A-10-8
Both Heads Dated A-8-8
68 427/390 HP Engine
Block dated A-10-8
Both Heads Dated A-8-8
They can be the correct head number for that car's application, and the date can be within a reasonable and acceptable time frame. However, there is no number on the head that MATCHES anything.
The only numbers that matter that actually match are the VIN on the body and the engine pad derivative and the transmission case.
Loosely, the trim tag color codes can match the body and interior colors.
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From: Oxford MA-----You just lost the game!!!!
New? Really? If people insist on using the ridiculous term "matching numbers" then VB's explanantion is the only one that makes sense. It was probably the original intention of the term but for whatever reason, people have chosen to complicate an otherwise simple issue. We would all be better off if it would just disappear from the entire collector car vocabulary, but that just ain't gonna happen. The genie is out of the bottle. I personally don't use it...anymore.
"numbers matching" means the number on the stamp pad matches the VIN. That's it. Nothing else. OK, fine, the tranny, too, but people don't seem to get as wrapped around the axle with the tranny as with the engine. Personally, I don't see what the big deal is......It has the original engine.....big deal. Does it have the original brake pads? Tires? Spark plugs? etc? probably not. Who cares, a nice car is a nice car.
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Melting Slicks
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From: Tolland CT
What if the VIN on the windshield pillar matches the number on the frame and transmission? 3 out of 4 make it matching numbers?
There's an article written several years ago which touched on the origins on matching numbers. It can be found in the C2 section. From memory, the original thought was if a Corvette had an engine block with the original VIN derivative it was probably low mileage and/or pampered since people would routinely pull them out and put another in its place if the original had any significant issues. A general indication the vehicle was worthy of restoration. Since this term now equates to a significant increase in value people go to great lengths to save the original block which would otherwise have been thrown away. Others made an industry of faking original blocks...
The article went into great detail regarding what matching numbers meant at that time. Much more than indication the block was original. Pretty much any part which had a part number and date code became part of the criteria for matching numbers.
There's an article written several years ago which touched on the origins on matching numbers. It can be found in the C2 section. From memory, the original thought was if a Corvette had an engine block with the original VIN derivative it was probably low mileage and/or pampered since people would routinely pull them out and put another in its place if the original had any significant issues. A general indication the vehicle was worthy of restoration. Since this term now equates to a significant increase in value people go to great lengths to save the original block which would otherwise have been thrown away. Others made an industry of faking original blocks...
The article went into great detail regarding what matching numbers meant at that time. Much more than indication the block was original. Pretty much any part which had a part number and date code became part of the criteria for matching numbers.
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From: Oxford MA-----You just lost the game!!!!
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From: Southbound
Cruise-In II Veteran
