Engine casting numbers ...
Thread Starter
Drifting
Joined: Nov 2012
Posts: 1,973
Likes: 865
Engine casting numbers ...
So I was told that the engine in my 71 is not the factory matching number unit ... no problem as not much on this car is factory matching anymore. Never the less I am curious to find out what is in there, I know it's a small block 3970010 but there is no VIN on the front right of the block, where else would I look for identifiers? I see the date clock not really positive how to read it there is a number 40CM next to the left of the casting number?
Anybody want to weigh in on this?
Dave
Anybody want to weigh in on this?
Dave
Team Owner
Joined: Sep 2006
Posts: 31,173
Likes: 4,250
From: Westminster Maryland
Hi Dave,
The 010 block was an extremely widely used block.
If there's no information on the front stamp pad there's no way to tell what it's configuration and use originally was.
Are you looking at the pad in front of the passenger's side head?
Have you looked to see if there is a date code on the block? It will be on the rear of the block just in front of the bell housing. That will at least tell you the age of the block.
I believe the 40CM identifies the mold used when the block was cast.
Regards,
Alan
The pad should look something like this.
The 010 block was an extremely widely used block.
If there's no information on the front stamp pad there's no way to tell what it's configuration and use originally was.
Are you looking at the pad in front of the passenger's side head?
Have you looked to see if there is a date code on the block? It will be on the rear of the block just in front of the bell housing. That will at least tell you the age of the block.
I believe the 40CM identifies the mold used when the block was cast.
Regards,
Alan
The pad should look something like this.
Last edited by Alan 71; Jan 1, 2013 at 03:55 PM.
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Phantom,
Alan gave you the best info.
The block if the date code is correct could be orig to car.
There is boundless info on the forum regarding vin#'s.
If the block went to a machine shop and was milled they
could have knocked off the numbers. "Decked"
An over the counter block had a production # on the vin pad
beginning with CE...... No vin number.
In the beginning of the c-3 production GM offered a 5 yr or 50,000
mile warranty which hurt em.
A '69 corvette could very easily have had a warranty engine installed
not exceeding the mileage now, a new motor as late as 1974.
If it was a short block they would swap out your top end onto a new block.
Now fast forward to NCRS group.
Why not start a warranty class for documented dealer installed replacement engines and trans?
Because as I understand it now it is a points deduction during judging.
What if a guy has a truly correct factory authorized CE engine.
Is this car more factual or historically correct than a modern restoration?
Leaves things to be considered down the road in Judging
Hope this helped you.
Marshal
Alan gave you the best info.
The block if the date code is correct could be orig to car.
There is boundless info on the forum regarding vin#'s.
If the block went to a machine shop and was milled they
could have knocked off the numbers. "Decked"
An over the counter block had a production # on the vin pad
beginning with CE...... No vin number.
In the beginning of the c-3 production GM offered a 5 yr or 50,000
mile warranty which hurt em.
A '69 corvette could very easily have had a warranty engine installed
not exceeding the mileage now, a new motor as late as 1974.
If it was a short block they would swap out your top end onto a new block.
Now fast forward to NCRS group.
Why not start a warranty class for documented dealer installed replacement engines and trans?
Because as I understand it now it is a points deduction during judging.
What if a guy has a truly correct factory authorized CE engine.
Is this car more factual or historically correct than a modern restoration?
Leaves things to be considered down the road in Judging
Hope this helped you.
Marshal
Thread Starter
Drifting
Joined: Nov 2012
Posts: 1,973
Likes: 865
Hi Dave,
The 010 block was an extremely widely used block.
If there's no information on the front stamp pad there's no way to tell what it's configuration and use originally was.
Are you looking at the pad in front of the passenger's side head?
Have you looked to see if there is a date code on the block? It will be on the rear of the block just in front of the bell housing. That will at least tell you the age of the block.
I believe the 40CM identifies the mold used when the block was cast.
Regards,
Alan
The pad should look something like this.
The 010 block was an extremely widely used block.
If there's no information on the front stamp pad there's no way to tell what it's configuration and use originally was.
Are you looking at the pad in front of the passenger's side head?
Have you looked to see if there is a date code on the block? It will be on the rear of the block just in front of the bell housing. That will at least tell you the age of the block.
I believe the 40CM identifies the mold used when the block was cast.
Regards,
Alan
The pad should look something like this.
Race Director
Joined: Oct 2000
Posts: 12,640
Likes: 3,103
From: Shamong, NJ
The 3970010 block was used in 68 as a 327, and from 69-79 as a 350; in cars, trucks and Corvettes. It came in both 2 bbl and 4 bbl versions, and with 2 or 4 bolt main caps.
The 010 is/was the correct block for your 71, but as others have said, without the stamp pad info, there's no way of knowing what it was in originally.
The block casting date is found on the flange at the rear of the block, where the bellhousing attaches. The date should be made up of 4 digits, a letter for the month, 2 numbers for the day of the month, and a final number for the year. A date of F211 would be June (F), 21st (21), 1971 (1). The "date clock" just shows the time of the shift, that the block was cast.
The casting number for the heads, is found under the valve cover, cast into the top of the head. All 71 small blocks used heads with the casting number 3973487.
The 010 is/was the correct block for your 71, but as others have said, without the stamp pad info, there's no way of knowing what it was in originally.
The block casting date is found on the flange at the rear of the block, where the bellhousing attaches. The date should be made up of 4 digits, a letter for the month, 2 numbers for the day of the month, and a final number for the year. A date of F211 would be June (F), 21st (21), 1971 (1). The "date clock" just shows the time of the shift, that the block was cast.
The casting number for the heads, is found under the valve cover, cast into the top of the head. All 71 small blocks used heads with the casting number 3973487.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
P
Now fast forward to NCRS group.
Why not start a warranty class for documented dealer installed replacement engines and trans?
Because as I understand it now it is a points deduction during judging.
What if a guy has a truly correct factory authorized CE engine.
Is this car more factual or historically correct than a modern restoration?
Leaves things to be considered down the road in Judging
Hope this helped you.
Marshal
Now fast forward to NCRS group.
Why not start a warranty class for documented dealer installed replacement engines and trans?
Because as I understand it now it is a points deduction during judging.
What if a guy has a truly correct factory authorized CE engine.
Is this car more factual or historically correct than a modern restoration?
Leaves things to be considered down the road in Judging
Hope this helped you.
Marshal
1) There's no way of connecting a CE engine to a particular car. It might be a genuine dealer warranty replacement or it might have spent the last 30 years in a taxi cab or your Mom's old Biscayne til it was installed in a Corvette last week.
2) NCRS judges 'as delivered to the first owner', no better no worse. No car was delivered to it's first owner with a CE engine.
Sorry.
Last edited by Mike Ward; Jan 1, 2013 at 09:16 PM.
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2nd Gear
Joined: Mar 2013
Posts: 2
Likes: 0
i have a 327 4bolt main casting number is gm 3970010 ? #v0717tda not sure what this is ? id number is t8j524547 can anyone tell me what exactly i have and perhaps how much it may be worth was told the steele crank alone is worth about 300.00 any help would be appreciated
Last edited by fishinbink; Mar 16, 2013 at 11:15 PM.
Race Director
Joined: Oct 2000
Posts: 12,640
Likes: 3,103
From: Shamong, NJ
Something doesn't make sense with your numbers. The TDA suffix code was either a 72 307 in a 10 or 20 series truck, or a 350 in a 1980 10 or 15 series truck.
The 010 block was used for 68 327's in "A" bodies (Chevelle & El Camino), and 69-79 as 350's. Neither of these combinations work with the TDA suffix code.
The 010 block was used for 68 327's in "A" bodies (Chevelle & El Camino), and 69-79 as 350's. Neither of these combinations work with the TDA suffix code.
2nd Gear
Joined: Mar 2013
Posts: 2
Likes: 0
they don't make sense to me either but they are stamped clearly on the block i will try to get pics to put on here so maybe somebody will be able to help me out i will double check but the first time i tried to research this i found a place that said there was a shortage of blocks needed and that some came from a truck plant in tocowanda in order to help supply the demand for the corvettes now i can't remember where i found that but it came from researching the numbers. if it is a true 327 4bolt main what would approximate value be? any idea
Last edited by fishinbink; Mar 17, 2013 at 01:21 AM.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
Why are you convinced that it's 327 and not a 350? The casting number and assembly suffix code TDA indicates that it's from a 1980 light truck.
The story you heard about blocks from Tonawanda being used in Corvettes does not apply to this casting number. If it was 3970014, that's different.
The story you heard about blocks from Tonawanda being used in Corvettes does not apply to this casting number. If it was 3970014, that's different.
Race Director
Joined: Oct 2000
Posts: 12,640
Likes: 3,103
From: Shamong, NJ
I think the 1980 TDA truck 350, used either a 14010207 or 209 block??? Or maybe a 14016379?
The story you heard about blocks from Tonawanda being used in Corvettes does not apply to this casting number. If it was 3970014, that's different.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
I don't think the 80 TDA truck 350, used the 010 block. Chevrolet switched to the right hand dipstick, for 1980, and the blocks got 8 digit casting numbers, starting with 140xxxxx.
I think the 1980 TDA truck 350, used either a 14010207 or 209 block??? Or maybe a 14016379?
I think the 1980 TDA truck 350, used either a 14010207 or 209 block??? Or maybe a 14016379?
There again was the 0010 ever used for a 307 cu. in?