Engine pad stamping ?
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 331
From: Indy Indiana
As stated, check the casting number of your block and the casting date of your block to confirm the "blew up in the 1st 2 weeks" theory.. with an assembly in 1974 and your casting code/date, I expect that your theory will unravel..
the 1974 block would be a '289' block and the 71 block will be a '512' block. the '289' block would most likely be the much lower horsepower with the lower compression/cam configuration etc.. of that era. I doubt that your 1974 warranty replacement engine is built exactly as a 71 LS5 would be configured..
it would be replaced as a short block assembled at the factory with the specs at the time ( 1974) and not the specs of 3 years earlier. Unless the dealer acquired a empty short block and transferred your 2000 mile components pistons/cam/crank etc. into your new block.. I doubt that any did that.. they would not put old parts inside a new block.
someone tell me if I am all wet in this theory..
paint on the pad also means that the engine has more likely been out for some reason since initial installation for rebuild/repair sometime after the CE engine was put in.. perhaps even years or decades later..
if you follow the logic and comments of these posts, I think your stated history from your previous owners is BS.
the 1974 block would be a '289' block and the 71 block will be a '512' block. the '289' block would most likely be the much lower horsepower with the lower compression/cam configuration etc.. of that era. I doubt that your 1974 warranty replacement engine is built exactly as a 71 LS5 would be configured..
it would be replaced as a short block assembled at the factory with the specs at the time ( 1974) and not the specs of 3 years earlier. Unless the dealer acquired a empty short block and transferred your 2000 mile components pistons/cam/crank etc. into your new block.. I doubt that any did that.. they would not put old parts inside a new block.
someone tell me if I am all wet in this theory..
paint on the pad also means that the engine has more likely been out for some reason since initial installation for rebuild/repair sometime after the CE engine was put in.. perhaps even years or decades later..
if you follow the logic and comments of these posts, I think your stated history from your previous owners is BS.
Team Owner
Joined: Feb 2005
Posts: 35,976
Likes: 29
From: San Clemente California
As stated, check the casting number of your block and the casting date of your block to confirm the "blew up in the 1st 2 weeks" theory.. with an assembly in 1974 and your casting code/date, I expect that your theory will unravel..
the 1974 block would be a '289' block and the 71 block will be a '512' block. the '289' block would most likely be the much lower horsepower with the lower compression/cam configuration etc.. of that era. I doubt that your 1974 warranty replacement engine is built exactly as a 71 LS5 would be configured..
it would be replaced as a short block assembled at the factory with the specs at the time ( 1974) and not the specs of 3 years earlier. Unless the dealer acquired a empty short block and transferred your 2000 mile components pistons/cam/crank etc. into your new block.. I doubt that any did that.. they would not put old parts inside a new block.
someone tell me if I am all wet in this theory..
paint on the pad also means that the engine has more likely been out for some reason since initial installation for rebuild/repair sometime after the CE engine was put in.. perhaps even years or decades later..
if you follow the logic and comments of these posts, I think your stated history from your previous owners is BS.
the 1974 block would be a '289' block and the 71 block will be a '512' block. the '289' block would most likely be the much lower horsepower with the lower compression/cam configuration etc.. of that era. I doubt that your 1974 warranty replacement engine is built exactly as a 71 LS5 would be configured..
it would be replaced as a short block assembled at the factory with the specs at the time ( 1974) and not the specs of 3 years earlier. Unless the dealer acquired a empty short block and transferred your 2000 mile components pistons/cam/crank etc. into your new block.. I doubt that any did that.. they would not put old parts inside a new block.
someone tell me if I am all wet in this theory..
paint on the pad also means that the engine has more likely been out for some reason since initial installation for rebuild/repair sometime after the CE engine was put in.. perhaps even years or decades later..
if you follow the logic and comments of these posts, I think your stated history from your previous owners is BS.
100% Block casting number & date is the next step...
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
Ok, you're all wet.
The cars of this era were built with a 5/50 warranty. If the engine from a BBC '71 had blown in '76 when BBC Corvettes were no longer being made they wouldn't have told the owner tough luck, here's an L48 instead.
CE engines were built 'to order'. If an '71 LS5 went bang, GM supplied a replacement engine built to '71 LS5 specs. If they could use a more modern/current casting number block without affecting fit, form or function then they might have. Casting dates are irrelevant obviously.
The cars of this era were built with a 5/50 warranty. If the engine from a BBC '71 had blown in '76 when BBC Corvettes were no longer being made they wouldn't have told the owner tough luck, here's an L48 instead.
CE engines were built 'to order'. If an '71 LS5 went bang, GM supplied a replacement engine built to '71 LS5 specs. If they could use a more modern/current casting number block without affecting fit, form or function then they might have. Casting dates are irrelevant obviously.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,482
From: Southbound
Cruise-In II Veteran
I'll go with slightly damp. There is no real reason to check block numbers or casting dates on a CE block other than satisfying curiosity. The block is not original to the car. The story behind the replacement might add interest to the car, but does not add value.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
True, but it either blows the theory of two weeks 2,000 miles out of the water, or leaves it on the 'maybe' list.
I'd be curious to know if for no other reason than confirming that this is a 1974 CE engine as per the stamp pad.
I'd be curious to know if for no other reason than confirming that this is a 1974 CE engine as per the stamp pad.
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 331
From: Indy Indiana
people pay good money for a good story. .who knows what that $$ increment might be.. to some of us, we might pay more for a date correct engine and a higher probability story vs. a car with a random truck engine in it and a BS story.
to many people, it is part of the investment decision to buy the car or not and its upside potential.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
Incorrect casting number is 350 point deduct.
If that's OK but there's a non-typical casting date, it's a 175 point deduct instead.
If that's OK, the pad surface is worth 38 points, the engine assembly code is worth 25 points and the VIN derivative is worth 25 points.
The best this engine could do as-is would be a 88 point deduct. If the paint was removed so the pad surface could be properly seen, it might drop to a 50 point deduct for the assembly code and VIN derivative.
If that's OK but there's a non-typical casting date, it's a 175 point deduct instead.
If that's OK, the pad surface is worth 38 points, the engine assembly code is worth 25 points and the VIN derivative is worth 25 points.
The best this engine could do as-is would be a 88 point deduct. If the paint was removed so the pad surface could be properly seen, it might drop to a 50 point deduct for the assembly code and VIN derivative.
Safety Car
Joined: Nov 2003
Posts: 4,274
Likes: 6
From: Corvetteville USA
Incorrect casting number is 350 point deduct.
If that's OK but there's a non-typical casting date, it's a 175 point deduct instead.
If that's OK, the pad surface is worth 38 points, the engine assembly code is worth 25 points and the VIN derivative is worth 25 points.
The best this engine could do as-is would be a 88 point deduct. If the paint was removed so the pad surface could be properly seen, it might drop to a 50 point deduct for the assembly code and VIN derivative.
If that's OK but there's a non-typical casting date, it's a 175 point deduct instead.
If that's OK, the pad surface is worth 38 points, the engine assembly code is worth 25 points and the VIN derivative is worth 25 points.
The best this engine could do as-is would be a 88 point deduct. If the paint was removed so the pad surface could be properly seen, it might drop to a 50 point deduct for the assembly code and VIN derivative.
Any thoughts on how this would compare to a similar car that had an original motor in it?
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Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,482
From: Southbound
Cruise-In II Veteran
In this specific instance with this car, the OP is wanting to sell. He is not concerned with judging.
Checking the numbers and dates on the CE will be something for a potential buyer, provided numbers and dates matters to that person.
Checking the numbers and dates on the CE will be something for a potential buyer, provided numbers and dates matters to that person.
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
This is GREAT information on the points but I would like to know what $$$$ deduction are we talking on a car like this? The OP's threads on this car dealt with selling the car, condition, pricing, etc.
Any thoughts on how this would compare to a similar car that had an original motor in it?
Any thoughts on how this would compare to a similar car that had an original motor in it?
I've wondered the same at times. I've never heard of any data being gathered to track typical sales prices for 'correct' NOMs. I rarely see a NOM Corvette for sale other than restomods. Seems all we have to go by are individual opinions dependent on how much weight the responder puts on matching numbers.
I've heard figures from 20% to 50% off depending on whether we're talking about a base model or a high performance package. This is just speculation, no data to support these numbers.
Team Owner
Joined: Feb 2005
Posts: 35,976
Likes: 29
From: San Clemente California
Team Owner
Joined: Feb 2005
Posts: 35,976
Likes: 29
From: San Clemente California
I've wondered the same at times. I've never heard of any data being gathered to track typical sales prices for 'correct' NOMs. I rarely see a NOM Corvette for sale other than restomods. Seems all we have to go by are individual opinions dependent on how much weight the responder puts on matching numbers.
I've heard figures from 20% to 50% off depending on whether we're talking about a base model or a high performance package. This is just speculation, no data to support these numbers.
Not that I would ever consider buying a CE block car, never have and don't think I ever will but 20-50% sounds about right. His car if documented and all other component stamps match as he indicates they do, 20% under current market sounds about right.
Safety Car
Joined: Nov 2003
Posts: 4,274
Likes: 6
From: Corvetteville USA
I am certain others like you would ever consider buying a CE block car as well. This hurts value considerably. All about supply and demand.
Simply put, even though the supply of CE block cars are not high (that I know of) there is no demand for them by collectors.
Team Owner
Joined: Feb 2005
Posts: 35,976
Likes: 29
From: San Clemente California
Yes, the current market would not price a CE car out equal to one that had an original motor in.
I am certain others like you would ever consider buying a CE block car as well. This hurts value considerably. All about supply and demand.
Simply put, even though the supply of CE block cars are not high (that I know of) there is no demand for them by collectors.
I am certain others like you would ever consider buying a CE block car as well. This hurts value considerably. All about supply and demand.
Simply put, even though the supply of CE block cars are not high (that I know of) there is no demand for them by collectors.
Team Owner
Joined: Sep 2002
Posts: 38,351
Likes: 2,077
From: California
Hey everyone, I think I ate another bad batch of Corn Flakes!
Should I then say what I am thinking?????????
PS I should have said that- built in 1974-- they would have pulled whatever heads and cams of that year vintage (1974) for the build of this CE block (thus probably LS-4 level). Actually I would also like to know the bore of the cylinders, to see or guess how many rebuilds this CE has had since getting uncrated and installed and then rebuilt and rebuilt again! I will put money on 60 over!!!!!!! In the betting pool!!!!!
PS I should have said that- built in 1974-- they would have pulled whatever heads and cams of that year vintage (1974) for the build of this CE block (thus probably LS-4 level). Actually I would also like to know the bore of the cylinders, to see or guess how many rebuilds this CE has had since getting uncrated and installed and then rebuilt and rebuilt again! I will put money on 60 over!!!!!!! In the betting pool!!!!!
Last edited by TCracingCA; Dec 19, 2013 at 05:32 PM.
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
CE engines were built 'to order'. If an '71 LS5 went bang, GM supplied a replacement engine built to '71 LS5 specs. If they could use a more modern/current casting number block without affecting fit, form or function then they might have. Casting dates are irrelevant obviously.
If I could get a NOM that is complete in every other aspect for 50% less, would I choose it over the exact same car but with an original motor? You betcha.
Melting Slicks
Joined: Oct 2003
Posts: 2,187
Likes: 830
From: Chapel Hill NC
2025 c3 ('68-'73) of the Year Finalist - Unmodified
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The only reason I bought my 68 BB tripower red convertible with chrome Hooker header side pipes was because it was a NOM. I couldn't have afforded it otherwise.
Safety Car
Joined: Nov 2003
Posts: 4,274
Likes: 6
From: Corvetteville USA
Reread Mike's post:
As far as the demand for a CE motor goes, there is no such thing. As usual, I think people are overstating the importance of an original motor. If you are concerned about judging, you can still receive a Top Flight Award with a NOM.
If I could get a NOM that is complete in every other aspect for 50% less, would I choose it over the exact same car but with an original motor? You betcha.
As far as the demand for a CE motor goes, there is no such thing. As usual, I think people are overstating the importance of an original motor. If you are concerned about judging, you can still receive a Top Flight Award with a NOM.
If I could get a NOM that is complete in every other aspect for 50% less, would I choose it over the exact same car but with an original motor? You betcha.
Last edited by theblackvette; Dec 20, 2013 at 07:58 AM.
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
As far as this car on this thread and the thread that was closed it is all about the money. I am certain what you say is fact about judging but lets look at value. Can one expect to find a buyer to pay top dollar Barret Jackson pro team type prices for a 1971 LS5 corvette? I would say yes if you advertise with clever choice of words and roll it on an auction floor. But to sell to an educated collector? Not a chance. Will never happen.
You are much more versed in the going rates of '71 LS5s, but 50% less for an NOM being the only difference?
Team Owner
Joined: Feb 2005
Posts: 35,976
Likes: 29
From: San Clemente California
As far as this car on this thread and the thread that was closed it is all about the money. I am certain what you say is fact about judging but lets look at value. Can one expect to find a buyer to pay top dollar Barret Jackson pro team type prices for a 1971 LS5 corvette? I would say yes if you advertise with clever choice of words and roll it on an auction floor. But to sell to an educated collector? Not a chance. Will never happen.
There is a market for every car, I always say there is an *** for every seat but collectors and dealers; believe it or not, are the top buyers of rare BB cars, LT1's etc.
They have the money so why buy a NOM when there are plenty of documented matching numbers C3's out there to be had. Among other muscle cars, we sell a lot of C3's, they are popular and move fairly quickly plus, I like em but the main reason they sell well is because we only buy the rarest cars with good owner history, paperwork and matching numbers drivetrains.
We have established a good client base over the years so they know where to come for original cars. If I told any of my clients that a particular car is a NOM or the trim and color has been changed in anyway, they would likely stay clear or it or at a min they would low ball the heck out of it.
A PITA I'd rather not have to deal with.