Ls1 or ls6 engine 12561168??
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Ls1 or ls6 engine 12561168?? Hi everyone.
trying to work out what my engine actually is from factory.
Block casting number is 12561168 and for all purposes makes it a ls6 bottom end.
Inlet and exhaust manifold are ls6 items.
But the cylinder heads are 241 casting.
engine is out of a 2004 vy lx8 adventra awd sports wagon in Australia if that makes any difference.
From my understanding Holden ordered them this way from GM for what reason I have no idea.
Or is it just a run of the mill ls1 that has used a ls6 block and manifolds??
trying to work out what my engine actually is from factory.
Block casting number is 12561168 and for all purposes makes it a ls6 bottom end.
Inlet and exhaust manifold are ls6 items.
But the cylinder heads are 241 casting.
engine is out of a 2004 vy lx8 adventra awd sports wagon in Australia if that makes any difference.
From my understanding Holden ordered them this way from GM for what reason I have no idea.
Or is it just a run of the mill ls1 that has used a ls6 block and manifolds??
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My Monaro is a 2004 that I bought brand new. I understood at the time that VY Series 2 and VZ LS1 engines were a hybrid ordered by Holden for our cars, using LS1 parts that were being phased out with the end of the Camaro etc and the move of the Corvette to LS2. However, that may be wrong and also they were actually used elsewhere in the GM world. I don't know the US spec car details.
I read these 2004 VY II and 2005 VZ engines had the following over the 2003 VY engines.
*Still used 241 heads*
LS6 block
LS6 manifold
LS6 valley breather
Stronger floating pins
Bushed conrods
Revised pistons
LS2 head bolt configuration
Better design oil pan.
The US spec 2004 LS1 GTO had a revised cam (plus a couple of other changes) on top of this.
I read these 2004 VY II and 2005 VZ engines had the following over the 2003 VY engines.
*Still used 241 heads*
LS6 block
LS6 manifold
LS6 valley breather
Stronger floating pins
Bushed conrods
Revised pistons
LS2 head bolt configuration
Better design oil pan.
The US spec 2004 LS1 GTO had a revised cam (plus a couple of other changes) on top of this.
Last edited by Pulse Red; Jan 2, 2023 at 05:05 AM.
Thread Starter
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My Monaro is a 2004 that I bought brand new. I understood at the time that VY Series 2 and VZ LS1 engines were a hybrid ordered by Holden for our cars, using LS1 parts that were being phased out with the end of the Camaro etc and the move of the Corvette to LS2. However, that may be wrong and also they were actually used elsewhere in the GM world. I don't know the US spec car details. I read these 2004 VY II and 2005 VZ engines had the following over the 2003 VY engines. 241 headsLS6 blockLS6 manifoldLS6 valley breatherStronger floating pinsBushed conrodsRevised pistonsLS2 head bolt configurationBetter design oil pan. The US spec 2004 LS1 GTO had a revised cam (plus a couple of other changes) on top of this.
So completely different to the USA system.
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Our US friends will confirm, but I don't think in 2004, GM were selling any alloy LS1 5.7s. Holden were the only customer for this engine.
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Australia didn't ever get any actual LS6 engines. Only LS1. No Aussie LS1 ever had the 243 heads either, just the changes I listed above for the 2004 onwards LS1s. I believe if your VIN says 04, you have the LS1 spec I listed.Our US friends will confirm, but I don't think in 2004, GM were selling any alloy LS1 5.7s. Holden were the only customer for this engine.
6G1YM84F54L203003
The search i did come back as a completely different car all together.
car is a vy 2 holden adventra awd sports wagon. 2004 model.
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Vin is
6G1YM84F54L203003
The search i did come back as a completely different car all together.
car is a vy 2 holden adventra awd sports wagon. 2004 model.
6G1YM84F54L203003
The search i did come back as a completely different car all together.
car is a vy 2 holden adventra awd sports wagon. 2004 model.
Thread Starter
On The Tree
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I thought it was sorted by 2004 but a lot of earlier LS1s around 2001 to 2003 were swapped for rebuilt LS1s due to oil consumption issues. My 2002 VX II SS was purchased new by me and had this done and I don't understand how Holden were allowed to provide my car an older engine but they did. Perhaps your donor car was given a replacement engine.
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I thought it was sorted by 2004 but a lot of earlier LS1s around 2001 to 2003 were swapped for rebuilt LS1s due to oil consumption issues. My 2002 VX II SS was purchased new by me and had this done and I don't understand how Holden were allowed to provide my car an older engine but they did. Perhaps your donor car was given a replacement engine.
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No it's the original engine. Just weird that Holden used ls6 short motors with all ls6 manifolds but opted for the ls1 241 cylinder heads.I've been told that all ls1 engines from vx onwards used this type of built engine from factory. why the hell would a factory opt for only 3/4 of a ls6 engine with cylinder heads that don't match the GM factory engines.
Nah, I don't think that's right. People get confused because the VX got the LS6 manifold, they thought it was an LS6 block too. As I say, I also had a VXII SS. I'm confident you will find the only cars that got the LS6 block were 04 onwards, along with the extras I listed. The part LS6 is for the reasons I listed above. They wouldn't use actual LS6 heads, they were expensive with sodium filled valves etc.
Last edited by Pulse Red; Jan 2, 2023 at 05:59 AM.
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Nah, I don't think that's right. People get confused because the VX got the LS6 manifold, they thought it was an LS6 block too. As I say, I also had a VXII SS. I'm confident you will find the only cars that got the LS6 block were 04 onwards, along with the extras I listed. The part LS6 is for the reasons I listed above. They wouldn't use actual LS6 heads, they were expensive with sodium filled valves etc.
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I know a limited number of ls2 engines in the change over received the 243 heads. But they are 6L blocks with the ls6 243 heads fitted.not sure what they came out in but wasn't a lot of them in Australia. I know of 1 engines that came out of a vz ss that's in a hatchback torana that has the 243 heads on it. All factory fitted.
In the US, 12561168 = LS6 block, used 2001+ to build both LS1 & LS6 engines.
A small percentage of fbody's got 12561168 = LS6 block for their LS1 engines in 2001. By 2002, roughly 20 to 25% of fbody LS1 engines used an LS6 block with 241 heads.
In my opinion, an LS6 block can be built to LS6 specs or better and be a defacto LS6 engine. I've had a spare LS6 block for 20+ years, I'd planned to do that with until learning the LS6 block is the weakest aluminum block the LS1/LS6 Gen 3 family. We used a seasoned early LS1 block for my 383 LS stroker instead of that LS6 block for that reason. The LS6 block can excel better at NA high rpm applications.
A small percentage of fbody's got 12561168 = LS6 block for their LS1 engines in 2001. By 2002, roughly 20 to 25% of fbody LS1 engines used an LS6 block with 241 heads.
In my opinion, an LS6 block can be built to LS6 specs or better and be a defacto LS6 engine. I've had a spare LS6 block for 20+ years, I'd planned to do that with until learning the LS6 block is the weakest aluminum block the LS1/LS6 Gen 3 family. We used a seasoned early LS1 block for my 383 LS stroker instead of that LS6 block for that reason. The LS6 block can excel better at NA high rpm applications.
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In the US, how was it decided which Camaro got the LS6 block? Or was it random?
What I was always told was that here in Australia, due to the distance, Holden would order a certain number of LS engines fron GM well before the cars were produced. So, we would always have the older engines until the 4th Gen F body cars were ceasing production (mid 2002) and the Corvette was the only other car running the 5.7 alloy LS1 before it moved to the LS2. Then we got the latest spec engines.
I'm unsure if the cutover for us was in 2003 or 2004 but was told by those who should know that for us, the upgraded version had 04 in the engine number.So, we had the older spec LS1 block cars into 2003 and then got the LS6 block cars for 2004.
We also got the LS2 for HSV when the Corvette did, which was a big deal because we usually were behind as mentioned. HSV could control their production numbers too, being more limited editions, Holden really couldn't.
What I was always told was that here in Australia, due to the distance, Holden would order a certain number of LS engines fron GM well before the cars were produced. So, we would always have the older engines until the 4th Gen F body cars were ceasing production (mid 2002) and the Corvette was the only other car running the 5.7 alloy LS1 before it moved to the LS2. Then we got the latest spec engines.
I'm unsure if the cutover for us was in 2003 or 2004 but was told by those who should know that for us, the upgraded version had 04 in the engine number.So, we had the older spec LS1 block cars into 2003 and then got the LS6 block cars for 2004.
We also got the LS2 for HSV when the Corvette did, which was a big deal because we usually were behind as mentioned. HSV could control their production numbers too, being more limited editions, Holden really couldn't.
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In the US, how was it decided which Camaro got the LS6 block? Or was it random? What I was always told was that here in Australia, due to the distance, Holden would order a certain number of LS engines fron GM well before the cars were produced. So, we would always have the older engines until the 4th Gen F body cars were ceasing production (mid 2002) and the Corvette was the only other car running the 5.7 alloy LS1 before it moved to the LS2. Then we got the latest spec engines. I'm unsure if the cutover for us was in 2003 or 2004 but was told by those who should know that for us, the upgraded version had 04 in the engine number.So, we had the older spec LS1 block cars into 2003 and then got the LS6 block cars for 2004. We also got the LS2 for HSV when the Corvette did, which was a big deal because we usually were behind as mentioned. HSV could control their production numbers too, being more limited editions, Holden really couldn't.
In the US, 12561168 = LS6 block, used 2001+ to build both LS1 & LS6 engines.
A small percentage of fbody's got 12561168 = LS6 block for their LS1 engines in 2001. By 2002, roughly 20 to 25% of fbody LS1 engines used an LS6 block with 241 heads.
In my opinion, an LS6 block can be built to LS6 specs or better and be a defacto LS6 engine. I've had a spare LS6 block for 20+ years, I'd planned to do that with until learning the LS6 block is the weakest aluminum block the LS1/LS6 Gen 3 family. We used a seasoned early LS1 block for my 383 LS stroker instead of that LS6 block for that reason. The LS6 block can excel better at NA high rpm applications.
A small percentage of fbody's got 12561168 = LS6 block for their LS1 engines in 2001. By 2002, roughly 20 to 25% of fbody LS1 engines used an LS6 block with 241 heads.
In my opinion, an LS6 block can be built to LS6 specs or better and be a defacto LS6 engine. I've had a spare LS6 block for 20+ years, I'd planned to do that with until learning the LS6 block is the weakest aluminum block the LS1/LS6 Gen 3 family. We used a seasoned early LS1 block for my 383 LS stroker instead of that LS6 block for that reason. The LS6 block can excel better at NA high rpm applications.
That would sound about right because the early ls1 engines had oil pump problems and excessive oil consumption but would mean the early ls1 block would be weaker than the later ls6 block and also the later ls6 had better oil gallery delivery system and oil pump than the first of the ls1 engines.
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I may have misunderstood the figures put forward by 99 Black Bird T/A. I thought it was being said that a portion of the Camaro were getting LS6 (up to 25%) and the rest of them were LS1 still until the end of production in mid 2002. So, in the USA, was it a running change to move from the LS1 to the LS6 block? In 2001 as mentioned by grinder11?