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lsx core shift

Old 05-01-2012, 12:35 PM
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Default lsx core shift

so how common was this problem? looking at a car with a first gen lsx block and was just trying to see how many people have actually seen or had this issue. talked to sdpc, the engine builder of this particular setup, and they said they have not had any such issues.

when i do an internet search you only see this occuring with boosted applications.

so is this something that is common or something that only takes place when you try to run boost on a 11:1 motor.
Old 05-01-2012, 12:43 PM
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Core shift isn't something that occurs when you run boost - it's a manufacturing defect that can cause things like oil galleys, cooling passages, cylinder bores, etc. to be slightly shifted (out of position). It's caused when the sand casting shifts in the mold as the molten metal is poured in to form the part (in this case, the engine block).

Core shift would likely be noticed by a good machinist that knows what he/she is doing...if it isn't shifted too much, a good machinist could fix the issue (there would have to be enough wall thickness so that they could shift whatever they needed to back into its correct position).
Old 05-01-2012, 01:28 PM
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so the car has 10k miles on the current setup. making 490 rwhp through a dana60. if something was going to happen would it have happened by now? or is it something that is still an issue. the motor was finished up mid 07 so im going to say it was one of the originals
Old 05-01-2012, 01:48 PM
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If the cylinder walls were thin or something else was misaligned, it likely would have shown up by now, but you really wouldn't know about something like a cylinder wall being thin unless you were trying to do a max effort build where you had hogged out as much as you possibly could.

Are you just buying it and tossing it in as is (no additional machine work), or are you rebuilding the short block? If you freshen up the short block, a good machinist would probably be able to tell if there were any issues. If it doesn't drink oil, cools properly, and there aren't any pistons sticking out of the side of the block, you will likely be fine.
Old 05-01-2012, 01:58 PM
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I wasn't planning on doing anything with it. Its in a car that is for sale. The only thing I might do is put new heads and intake on.it. is 454 cu.in. maxed out on one of the original lsx blocks.

This motor was custom built from scoggin dickey. I'm just not wanting to change things around then it snap in half.
Old 05-01-2012, 02:10 PM
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I have a first gen LSX block and have seen core shift first hand in a different lsx block and what ull see if that the material in between the cyc walls is thinner than the one beside it, its very easy to see w your eyes and it would take a pretty stupid machinist to miss it, the first gen LSX blocks are actually the strongest of the bunch.

Ill try and find a pic to show what im talking about
Old 05-01-2012, 02:15 PM
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Go to google and click Images and type in ''lsx block core shift''

Firtst pic top left corner
Old 05-01-2012, 02:22 PM
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So more than likely sdpc wouldn't let it out the door then
Old 05-01-2012, 03:28 PM
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Originally Posted by KAOS
So more than likely sdpc wouldn't let it out the door then
Exactly...if they had tried boring a core-shifted block out in the process of making a 454, they probably would have punched through a cylinder wall in the process.
Old 05-01-2012, 04:07 PM
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That makes me feel a little better then. I'm ocd about these things and like to have an idea of what I'm.getting myself into
Old 05-01-2012, 08:04 PM
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Originally Posted by 1999FirehawkLS1
Go to google and click Images and type in ''lsx block core shift''

Firtst pic top left corner
Really? Excellent misleading post! That picture is of an actual GMPP display block designed to show all the different bores that could be achieved with the LSX block.
Old 05-02-2012, 07:03 AM
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thats the pic that got me started on this whole core shift thing. so that was just a display?
Old 05-02-2012, 08:47 AM
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Originally Posted by KAOS
thats the pic that got me started on this whole core shift thing. so that was just a display?
Yes, that was at one of the performance shows to display the meat between the cylinders with different bore sizes.
Old 05-02-2012, 09:05 AM
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Originally Posted by 1999FirehawkLS1
I have a first gen LSX block and have seen core shift first hand in a different lsx block and what ull see if that the material in between the cyc walls is thinner than the one beside it, its very easy to see w your eyes and it would take a pretty stupid machinist to miss it, the first gen LSX blocks are actually the strongest of the bunch.

Ill try and find a pic to show what im talking about
a pretty stupid machinist cannot see below the deck surface which is where the evidence of core shift lies...Unless you have x-ray vision, the only way to find core shift is to sonic test it. and even then, on a cast block there are no guarantees your going to find it as it can be as little as .010. which in a cast block without core shift can have that variance just cast into the cylinder wall thickenss.

Originally Posted by scphilli
Really? Excellent misleading post! That picture is of an actual GMPP display block designed to show all the different bores that could be achieved with the LSX block.
dont let it get out...thats the only ammunition he has left.
Old 05-02-2012, 12:58 PM
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Dude's brain must be core shifted with that misleading *** post.
Old 05-02-2012, 08:58 PM
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Nope... seen it first hand at a shop in Michigan....that may be a display but it looks the exactly the same as the core shifted block I seen in person
Old 05-02-2012, 09:11 PM
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My question is how can you tell which blocks were bad. The motor in question has 10k miles on it but is it good to go or a ticking time bomb?
Old 05-02-2012, 09:15 PM
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U cant be 100% sure with out taken it apart really.....honestly if it came from sdpc id say its fine special w 10k already on it. SDPC knows there stuff n been selling for yrs and has a great rep. and customers service.
Old 05-02-2012, 11:28 PM
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Originally Posted by KAOS
so the car has 10k miles on the current setup. making 490 rwhp through a dana60.

sounds like that motor is down a 80-100RW
Old 05-03-2012, 12:14 AM
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Default Core shift stuff seems like bs to me

the only real thing that I have been able to find that was noticed with the LSX block was some of the castings did not come out right and started crumbling when honed. Even that I have no real proof. I have looked and looked and talked to a lot of people and every time someone had a core shift problem I was not able to verify. Here are pics of mine honed out to 4.125.





Seems like plenty of meat to me and block measures out correctly.

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