View Full Version : lsx core shift


KAOS
05-01-2012, 01:35 PM
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.

MeentSS02
05-01-2012, 01:43 PM
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).

KAOS
05-01-2012, 02:28 PM
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

MeentSS02
05-01-2012, 02:48 PM
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.

KAOS
05-01-2012, 02:58 PM
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.

1999FirehawkLS1
05-01-2012, 03:10 PM
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

1999FirehawkLS1
05-01-2012, 03:15 PM
Go to google and click Images and type in ''lsx block core shift''

Firtst pic top left corner

KAOS
05-01-2012, 03:22 PM
So more than likely sdpc wouldn't let it out the door then

MeentSS02
05-01-2012, 04:28 PM
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.

KAOS
05-01-2012, 05:07 PM
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

scphilli
05-01-2012, 09:04 PM
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.

KAOS
05-02-2012, 08:03 AM
thats the pic that got me started on this whole core shift thing. so that was just a display?

87silverbullet
05-02-2012, 09:47 AM
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.

bww3588
05-02-2012, 10:05 AM
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.

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.

:secret: dont let it get out...thats the only ammunition he has left.

87silverbullet
05-02-2012, 01:58 PM
Dude's brain must be core shifted with that misleading ass post.

1999FirehawkLS1
05-02-2012, 09:58 PM
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

KAOS
05-02-2012, 10:11 PM
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?

1999FirehawkLS1
05-02-2012, 10:15 PM
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.

NemeSS
05-03-2012, 12:28 AM
so the car has 10k miles on the current setup. making 490 rwhp through a dana60.:confused:
sounds like that motor is down a 80-100RW:huh:

thobart
05-03-2012, 01:14 AM
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.

http://i428.photobucket.com/albums/qq10/thobart/IMG_0243.jpg

http://i428.photobucket.com/albums/qq10/thobart/IMG_0242.jpg

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

driver56
05-03-2012, 01:23 AM
I noticed the blocks I've seen personally have the same foundry mark as iron blocks and heads from World Products. No real evidence of core shift either.

bww3588
05-03-2012, 01:25 AM
You can't be 100% sure unless you sonic test it or bore thru the wall. Core shift is not something you can see with the naked eye.

1999FirehawkLS1
05-03-2012, 01:44 AM
:confused:
sounds like that motor is down a 80-100RW:huh:

Ya but depends on the Heads, Cam, and A TH400 stalled will kill it w that S60 also...

thobart
05-03-2012, 01:45 AM
no evidence of true core shift. There has been a lot of finger pointing to photos of an LSX block honed out to different bore sizes per cylinder that has been represented as core shift. While you may not be able to prove exactly that a block has been core shifted without a sonic test does it matter if the block is strong and machines out correctly. Core shift is a casting problem where a block has not had the metal pored correctly during the casting process. It is either going to be weaker or not true for the bores in the block. All I am saying is the one I have has been as true as any other block I have dealt with. So all you can say is that the block may be less strong in some way. I have seen no evidence (and I have looked all over for it) that I can verify that anyone has had a real big problem with these blocks. I have heard but again not able to verify that some of them had material problems that exhibited in the machining process. I would think that some of the vendors on the board would be able to say something to this if it was a real problem.


You can't be 100% sure unless you sonic test it or bore thru the wall. Core shift is not something you can see with the naked eye.

1999FirehawkLS1
05-03-2012, 01:51 AM
I dont think it was a real big prb cuz before I bought Mine used I called GMPP and ran the Casting numbers threw there Engineering Dept and they acted like there was a few before they hit the market they knew about but none after the RnD stages...but Of course there prb goin to tell us what we wanna here also

KAOS
05-03-2012, 07:12 AM
Its down in power because of the ls6 heads and intake. I'd say it would be quite a performer with the right heads and intake

Jontall
05-03-2012, 08:03 AM
Core shift is scary because of the investment made. That core-shifted boosted GMPP 454 LSX crate motor over at Camaro5.com cracked like an egg and GM said the warranty was voided because of boost. The only way I'd use the LSX block is to have it sonic tested before I buy it.

KAOS
05-03-2012, 08:06 AM
Core shift is scary because of the investment made. That core-shifted boosted GMPP 454 LSX crate motor over at Camaro5.com cracked like an egg and GM said the warranty was voided because of boost. The only way I'd use the LSX block is to have it sonic tested before I buy it.

that is my concern. i dont want to be out all of this money on a car then all of a sudden have to replace the motor

87silverbullet
05-03-2012, 08:18 AM
Core shift is scary because of the investment made. That core-shifted boosted GMPP 454 LSX crate motor over at Camaro5.com cracked like an egg and GM said the warranty was voided because of boost. The only way I'd use the LSX block is to have it sonic tested before I buy it.

You really listen to anybody on camaro5? If thats the same thread I'm thinking about tell the whole truth about it. There is more to it than just "boost" and "cracked like an egg"

1999FirehawkLS1
05-03-2012, 12:19 PM
Core shift is scary because of the investment made. That core-shifted boosted GMPP 454 LSX crate motor over at Camaro5.com cracked like an egg and GM said the warranty was voided because of boost. The only way I'd use the LSX block is to have it sonic tested before I buy it.

Ah can we say 454 = Thin Walls = Why no one ever build a turbo motor lsx 454...... lol