LS6 Question
Thread Starter
Drifting
Joined: Sep 2007
Posts: 1,679
Likes: 1
From: Pendleton IN
LS6 Question
I have a block that I am thinking about purchasing. It is supposedly an LS6 original. I am not well versed in this area. This is what I have been told.
The stamping has a 10B prefix. I have not seen the block yet but was told that all LS6 prefixes were stamped like this one. My engine guy told me not to buy it because all LS6 engine prefixes should be 188, not 10B???????? I have access to some factory aluminum heads and thought that this block would be a good fit for a neat 54 screamer!
Any help would be appreciated.
The stamping has a 10B prefix. I have not seen the block yet but was told that all LS6 prefixes were stamped like this one. My engine guy told me not to buy it because all LS6 engine prefixes should be 188, not 10B???????? I have access to some factory aluminum heads and thought that this block would be a good fit for a neat 54 screamer!
Any help would be appreciated.
Last edited by 53 Blue Flame Brett; Mar 7, 2009 at 11:13 PM.
Melting Slicks
Joined: Jan 2003
Posts: 2,877
Likes: 13
From: Doha
St. Jude Donor '08
IMHO, being a LS6 block is not something special by itself (unless you're looking for a specific prefix and date), simply all 512 blocks are the same, even the 2 bolts mains ones will convert very easily into 4 bolts, even the legendary L88 engines use the 512 blocks.
I see many 512 blocks for sale and for cheap costs.
I see many 512 blocks for sale and for cheap costs.
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
Unless you're attempting to restore a genuine LS6 car (in which case this would still yield a NOM), or if you're going to track down the original car from which it came (might have long since passed into the great junk yard in the sky), as long as it's a serviceable ...512 BB cylinder case I just can't see what the fuss would be about a stamping, since if you've seen one you've pretty much seen the all. Tho fundamental to a sound engine build, the block really doesn't have all that much to do with whether you'll put together a screamer or a dog.
Bottom line, IMHO there are far better things about which to concern one's self when shopping for a block. My $.02, free of charge.
TSW
Bottom line, IMHO there are far better things about which to concern one's self when shopping for a block. My $.02, free of charge.
TSW
Last edited by TheSkunkWorks; Mar 8, 2009 at 04:35 AM.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
As others have said, nothing special about an LS6 block, any 4-bolt block will do.
Thread Starter
Drifting
Joined: Sep 2007
Posts: 1,679
Likes: 1
From: Pendleton IN
I fully understand that any BB will make a good screamer, especially in a 54 Corvette.
My goal is to determine if the block actually started life as an LS6, according to the stamping prefix of 10B.
Thanks for any help with this question.
My goal is to determine if the block actually started life as an LS6, according to the stamping prefix of 10B.
Thanks for any help with this question.
Thread Starter
Drifting
Joined: Sep 2007
Posts: 1,679
Likes: 1
From: Pendleton IN
A 70 Corvette engine would be stamped 70S..., maybe the Chevelle was different but I would think the stamp is 70B which would be a 70 built at Baltimore which is where the Chevelles were built. Not sure what the 188 would mean.
As others have said, nothing special about an LS6 block, any 4-bolt block will do.
As others have said, nothing special about an LS6 block, any 4-bolt block will do.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
I found out that the 10B would be correct for a 70 Chevelle built at Baltimore,
1....Chevy
0....1970
B....Baltimore Assembly
Chevelles were also built at Arlington (R), Atlanta (A), Flint (F), Kansas City (K), Van Nuys (L) and Oshawa (1).
The suffix stamps for LS6 would be CRR (Turbo 400) or CRV (M22).
All 70 LS6 blocks would be casting number 3963512.
There was an over the counter crate LS6 available for many years and it could use different block
casting numbers but all would be 4-bolt. It's suffix was XAA and no vin stamp should be present.
1....Chevy
0....1970
B....Baltimore Assembly
Chevelles were also built at Arlington (R), Atlanta (A), Flint (F), Kansas City (K), Van Nuys (L) and Oshawa (1).
The suffix stamps for LS6 would be CRR (Turbo 400) or CRV (M22).
All 70 LS6 blocks would be casting number 3963512.
There was an over the counter crate LS6 available for many years and it could use different block
casting numbers but all would be 4-bolt. It's suffix was XAA and no vin stamp should be present.
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Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 330
From: Indy Indiana
also check the oil galley holes above the oil filter boss, with 4 bolt blocks, the 3 holes will be 3/8 pipe thread, 1/2 pipe thread, and 1/2 pipe thread, 2 bolt blocks ( which are not LS6 blocks) will have 5/16 and 3/8 holes.. a counterfeited 4 bolt block may be machined for 4 bolt caps, but may not have the big oil holes.. real ls6 blocks will have both 4 bolt caps and big oil holes..
of course, just about anything can be remachined with 4 bolt caps and big oil holes, and re-stamped to just about anything... there is really no way to tell unless you have great documentation and a very small list of owners that you can consult..
probably the best you a can say it that " it appears to be"
- joe
of course, just about anything can be remachined with 4 bolt caps and big oil holes, and re-stamped to just about anything... there is really no way to tell unless you have great documentation and a very small list of owners that you can consult..
probably the best you a can say it that " it appears to be"
- joe
Intermediate
Joined: Oct 2008
Posts: 30
Likes: 0
I found out that the 10B would be correct for a 70 Chevelle built at Baltimore,
1....Chevy
0....1970
B....Baltimore Assembly
Chevelles were also built at Arlington (R), Atlanta (A), Flint (F), Kansas City (K), Van Nuys (L) and Oshawa (1).
The suffix stamps for LS6 would be CRR (Turbo 400) or CRV (M22).
All 70 LS6 blocks would be casting number 3963512.
There was an over the counter crate LS6 available for many years and it could use different block
casting numbers but all would be 4-bolt. It's suffix was XAA and no vin stamp should be present.
1....Chevy
0....1970
B....Baltimore Assembly
Chevelles were also built at Arlington (R), Atlanta (A), Flint (F), Kansas City (K), Van Nuys (L) and Oshawa (1).
The suffix stamps for LS6 would be CRR (Turbo 400) or CRV (M22).
All 70 LS6 blocks would be casting number 3963512.
There was an over the counter crate LS6 available for many years and it could use different block
casting numbers but all would be 4-bolt. It's suffix was XAA and no vin stamp should be present.
Suggest you inquire over at Chevelle Forum on this. If it really is a 70 LS-6 from a Chevelle, it is a rather rare piece and would probably be worth selling versus using as a core. There are a lot of BBC fans at Chevelle forum.
