Priceless? Worthless?
Melting Slicks
Joined: Sep 2005
Posts: 2,689
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From: Warminster PA
I agree 100%. I was just pointing out that casting numbers do get doctored - which does not apply to the block in question as it has a 396 casting number.
Drifting
Joined: May 2023
Posts: 1,330
Likes: 978
From: Sierra Vista, AZ
with your help I think I’ve come up with a logical explanation for my mystery block.
.......
The fact that my block is a virgin 427 has not been in question in my mind because after two machine shops inspected, measured, and determined it is a 427 I had it sonic tested for cylinder wall thickness, (besides passing the pencil test) and the measurements confirmed it is a 427.
.......
The fact that my block is a virgin 427 has not been in question in my mind because after two machine shops inspected, measured, and determined it is a 427 I had it sonic tested for cylinder wall thickness, (besides passing the pencil test) and the measurements confirmed it is a 427.
If I had the block, and a car that needed a 427 (or a 396 or a 454), I'd use it, and have fun driving around with a powerful engine.
but it is neat to see how folks can create wonderful narratives to explain things that have other more rational explanations.
Safety Car
Joined: Jul 2022
Posts: 3,930
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From: Eastern MA
I'm anxious to see what we learn from the numbers. A full breakdown on a block like this will be invaluable for people doing forum searches later. I'm confident that the knowledgeable members will be able to explain every character on the block.
Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
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Melting Slicks
Joined: Aug 2007
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From: Erwin, NC
OP clearly doesn't want to hear that it isn't a "virgin 427" block. We are shouting at a wall.
http://midamericachevelles.com/tech/bbsuffixcodes.html
The EJ in T1007EJ makes it a 396 cid / 360hp Chevelle with a manual transmission. It is either a "virgin 396" block or just another block that got bored to 427. Those are the only two options. Whether OP decides to accept it or not is irrelevant.
http://midamericachevelles.com/tech/bbsuffixcodes.html
The EJ in T1007EJ makes it a 396 cid / 360hp Chevelle with a manual transmission. It is either a "virgin 396" block or just another block that got bored to 427. Those are the only two options. Whether OP decides to accept it or not is irrelevant.
Burning Brakes
Joined: Sep 2014
Posts: 1,062
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From: Freehold NJ
My bet would be that he has a 396 block that has been bored to a 427. Machine shops aren't likely to research numbers, they are going to take a measurement - that is likely why they are telling him he has a 427 block. I doubt anyone could verify or say for sure if it was a virgin block that came from the factory that way but if in fact it did come from the factory that way, I would bet it is a GM machine shop boo-boo that some employee rescued from the scrap pile.
Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
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My bet would be that he has a 396 block that has been bored to a 427. Machine shops aren't likely to research numbers, they are going to take a measurement - that is likely why they are telling him he has a 427 block. I doubt anyone could verify or say for sure if it was a virgin block that came from the factory that way but if in fact it did come from the factory that way, I would bet it is a GM machine shop boo-boo that some employee rescued from the scrap pile.
Team Owner
Joined: Aug 2008
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From: Rochester NY
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Burning Brakes
Joined: Sep 2012
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I deal with 3 machine shop/engine builders and none of them do anything but address the casting number, date, and measure and assess the condition of the block, never do they claim original bore, other than by diameter. I would be interested to know if the valve relief setting on a 396 block would be the same as a 427. Can't see why it wouldn't, as the heads are the same per valve size. Never heard a variance of the relief in a 2.07/172 to a 2.19/172 to a 2.19/1.88 application, but I'd suspect they're all the same. Meanning the setup tooling would be the same, the bigger bore would just knock more of the big end away.
Burning Brakes
Joined: Sep 2014
Posts: 1,062
Likes: 379
From: Freehold NJ
When I read "virgin block" I assumed it was never assembled - as I'm reading this, I'm guessing that by "virgin" he just means he believes it wasn't machined? I agree with you that an anomaly block is not going to make the journey from machine shop to assembly plant.
Safety Car
Joined: Jul 2022
Posts: 3,930
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From: Eastern MA
there is not much to debate. the op post the block casting number of 962 which was cast from 1965 to very early 1966 that was four bolt main 396 used for solid lifter and early 396-360 engines in Chevelles the op posted the stamp pad of T1007EJ, 6Z08727 which is a 396/360 with K19, and manual trans built at the Freemont Ca assembly plant from a Chevelle assembled on Oct 7 1965. the vin of the car is for a car built the second week of Nov of 65. I would put the block casting date late sept of 65. this all jives and is correct but that is all on how the engine was in the fall of 1965.
I have said repeatedly that this discussion can be valuable, but I do not in any way mean that it is valuable in proclaiming this "427" a legit factory 427. It can have value in demonstrating how to use facts to run down the truth about an engine that any one of use might finds in a C2 without having to guess or take somebody's word for it..
Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
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if you think I am advocating any possibility of this block being originally a 427, you are mistaken. I am am not suggesting there's a debate to be made on the nature of this block.
I have said repeatedly that this discussion can be valuable, but I do not in any way mean that it is valuable in proclaiming this "427" a legit factory 427. It can have value in demonstrating how to use facts to run down the truth about an engine that any one of use might finds in a C2 without having to guess or take somebody's word for it..
I have said repeatedly that this discussion can be valuable, but I do not in any way mean that it is valuable in proclaiming this "427" a legit factory 427. It can have value in demonstrating how to use facts to run down the truth about an engine that any one of use might finds in a C2 without having to guess or take somebody's word for it..
Safety Car
Joined: Jul 2022
Posts: 3,930
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From: Eastern MA
this is a classic text book case on how to decode a Chevy block. Now this only applies on how it left GM assembly plants 60 years ago. What past owners and machine shops did is anyone's guess But there is no need to make up stories on it. This is like watching History Chanel's documentary's on Hitter after the bunker. Hell I think he want to the moon with JFK and his brother in 69 and not Armstrong and is living there in a village. If we want to make up stuff let's go all out
But this is exactly why the thread will have value.
Race Director
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From: north of Chicago
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So somebody pulled out an engine from a Chevelle (early in life) had it disassembled bored and set aside for 60 years. maybe got drafted and never got back to complete project of more power. No way its virgin if it was assembled at one time
Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
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wonder what the cost of buying a brand new 427 bare block from Chevy vs having a machine shop bore a 396 out?
Melting Slicks
Joined: Sep 2005
Posts: 2,689
Likes: 883
From: Warminster PA
Problem is you need to use the "thick walled" 396 blocks if you want to punch out a 396 to a 427. I believe the 4 bolt main blocks had the thicker cylinder walls, otherwise the cylinder wall becomes very thin and you run the possibility of poor cooling and the cylinder wall cracking. Not saying it can't be done, but.........
Race Director
Joined: Jan 2003
Posts: 17,632
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From: Central Arkansas
Here is one range of its potential worth.
https://www.ebay.com/sch/i.html?_nkw...490.m570.l1312
Cant see it being of any particular interest to Corvette restorers.
https://www.ebay.com/sch/i.html?_nkw...490.m570.l1312
Cant see it being of any particular interest to Corvette restorers.
Drifting
Joined: May 2023
Posts: 1,330
Likes: 978
From: Sierra Vista, AZ
Here is one range of its potential worth.
https://www.ebay.com/sch/i.html?_nkw...490.m570.l1312
Cant see it being of any particular interest to Corvette restorers.
https://www.ebay.com/sch/i.html?_nkw...490.m570.l1312
Cant see it being of any particular interest to Corvette restorers.
perhaps try again please?
or take a screen shot, so we can see what you see? ebay search is pretty useless these days, they show you a whole bunch of things that are NOT what you are searching for.
Melting Slicks
Joined: Apr 2013
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From: McCloud CA
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The block is not a Virgin 427 It's an alien 427 the reason being is it dose not exist. Nothing special just your common bored over and probably to much 396. Priceless? Nope 300-500