***[merged]L-92/LS-3 / 6.2 L blocks core/liner shift***
#1
***L-92/LS-3 / 6.2 L blocks are "junk"***
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***6.2 L-92/LS-3 blocks are "GARBAGE"***
I have just purchased the new L-92/LS-3 6.2 ltr block from GM and the casting and machining is PATHETIC to say the least!!! GM should be ashamed to release such garbage in quality control. I am on my third returned block from GM performance parts. Each block has come with the cylinders cast in a different position, so when the boring process was done at the factory,some of the cylinders are @.120 thick on one side and .040 on the other side!! Its as if the liners were just laid in the casting, not being held in place and then when the aluminum was cast around them, they moved. The bores are probably symetrical because they are indexed by a computer but the liners are not. Then theres the mains... You would not believe the amount of deburring that has to be done, its as if they ran the boring bar through at high speed leaving a .020 razor edge at one side of the mains.. and then they don,t even remove it! Just think they are using this block on the new high end trucks as well as...rumor has it.. the new supercharged Corvette! I don't know who is inspecting these blocks before shipping but they should be FIRED and i hope someone that has a friend of a friend that works in GM QA management reads this before they have a complete recall after these engines fail in the field. The liner was so thin on one block that if you added any power enhancment you would probably blow out the WALL.We are now on our third block and are trying to get a hold of a pre inspected block prior to shipping. Time will tell if we get a decent one to work with!!
***6.2 L-92/LS-3 blocks are "GARBAGE"***
I have just purchased the new L-92/LS-3 6.2 ltr block from GM and the casting and machining is PATHETIC to say the least!!! GM should be ashamed to release such garbage in quality control. I am on my third returned block from GM performance parts. Each block has come with the cylinders cast in a different position, so when the boring process was done at the factory,some of the cylinders are @.120 thick on one side and .040 on the other side!! Its as if the liners were just laid in the casting, not being held in place and then when the aluminum was cast around them, they moved. The bores are probably symetrical because they are indexed by a computer but the liners are not. Then theres the mains... You would not believe the amount of deburring that has to be done, its as if they ran the boring bar through at high speed leaving a .020 razor edge at one side of the mains.. and then they don,t even remove it! Just think they are using this block on the new high end trucks as well as...rumor has it.. the new supercharged Corvette! I don't know who is inspecting these blocks before shipping but they should be FIRED and i hope someone that has a friend of a friend that works in GM QA management reads this before they have a complete recall after these engines fail in the field. The liner was so thin on one block that if you added any power enhancment you would probably blow out the WALL.We are now on our third block and are trying to get a hold of a pre inspected block prior to shipping. Time will tell if we get a decent one to work with!!
#2
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The arrogance of some people amazes me. Hello, It's a truck motor!! Did you honestly think GM gives a flying flip about cylinder wall thickness in a power adder application after you run a boring bar through it? That isn't in their design parameters so why should they waste money (theirs and yours, BTW) over-engineering a product. If you talked to GM, I am sure they would gladly steer you towards an LS7 block which is designated for high performance. All the high performance L92 builds this year and next probably equal two hours of foundry and machine time total. If you want a race engine you are either going to have to buy one or put a little effort into building it. There isn't any free lunch in the hi-po world.
#3
Originally Posted by 96 Comp T/A
The arrogance of some people amazes me.
Todd
#5
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I'm no expert on the subject but I am pretty sure those blocks come ruff and need to be honed before being built. That's what everyone has been telling me anyway, they come unfinished from that factory as do most truck blocks.
#6
The block is completly finished! just as it is delivered to the line at the factory, For performance shops though this is not good enough, we/they usually do a hone with a torque plate bolted to the top of the deck to simulate head installation and distortion, since the factory doesnot hone/bore with a torque plate they hone a few thou larger to straiten up the bore.
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#8
I would have to ask if you have ever seen any lsx block before. The tolerances on the lsx engines are far superior to the sbc stuff that was produced for 40 years. My money says you are full of it and do not have the faintest idea of what you are talking about. Humility always involves getting your *** kicked a few times.
#10
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Originally Posted by WhiteDiamond
Your first sentence says volumes about your overall post. Truck motor or not has nothing to do with machining aspects of engine assembly. I will gurantee you that there are plenty of truck owners out there who run their motors as hard, if not harder, than many of the car owners.....Every heard of towing, pulling, or hauling?
Todd
Todd
I am constantly amazed by by the lack of intelligence exhibited by some of the "high performance enthusiasts" that I see on internet message boards. To expect a mass manufacturer to spend 1 cent more than nescesary in design, tooling or production of a product in order to insure durability at 200% or greater of the intended application is foolish. By calling something "junk" would mean that it doesn't perform well in it's intended application, which in this case is a truck engine, and is not the case. Out of all the 6.2 liter blocks GM is going to make this year, how many do you think are going to end up in a high output configuration 100-500? I can for sure tell you the number that will come from GM that way and the number is zero!GM probably will build 200,000 of these, in a calendar year! I don't think crying and whining on an internet message board about the fact that the cheap cast iron liners are not held in the optimal position for ultra high output applications is going to do anyone any good, least of all to the guy complaining about it. If this guy was serious about making horsepower he would be replacing said cheap, crooked cast iron liners with a sleeve made out of a proper material, that was intended for high performance applications. Said person may also want to consider some of his previous statements such as:
Originally Posted by klymaxr
You would not believe the amount of deburring that has to be done, its as if they ran the boring bar through at high speed leaving a .020 razor edge at one side of the mains..
And to White Diamond, You should really re-read klymax's post and then re-read mine. If you don't understand the difference between casting uniformity and finish machining you shouldn't have even opened your mouth:
Originally Posted by klymaxr
Each block has come with the cylinders cast in a different position, so when the boring process was done at the factory,some of the cylinders are @.120 thick on one side and .040 on the other side!!
Originally Posted by klymaxr
The bores are probably symetrical because they are indexed by a computer but the liners are not.
Originally Posted by WhiteDiamond
Truck motor or not has nothing to do with machining aspects of engine assembly.
#11
L92 block casting quality issues?
#14
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Originally Posted by NemeSS
WITHOUT PICS OF YOUR COMPLAINTS
EVRYONE IS GOIN TO GIVE U A HARD TIME
so post pics of what u are complaning about instead of just trying to
stir things up
PS VERY DETAILED PICS!!!!
#16
Originally Posted by The1N_only
how are you going to start a thread like this and not follow up... wtf?
#17
Not for nothing and I don't know this guy who posted this and I don't have any pictures, so take it for what its worth, but...
The LS7 blocks have been no better I hate to tell you.
I know of multiple people that have had to order "more than one" because the machining was so poor from the factory. (I am not saying all of them)
It wouldn't surprise me if the L-92 blocks were no better?
In addition, the people that have told me this are saying this in comparison to LS1/LS6 blocks and LS2 blocks, not C5R and race blocks. It seems the older blocks were made with more precision?
One of the bad blocks was actually part of an LS7 crate engine that was going to be upgraded. I quote: "I thought these engines were hand built?"
It is unfortunate because I actually want to get an LS7 block myself.
I know it is not good news, but I don't think this guy is telling tall tails.
This is just an FYI, I won't be back in this thread to defend myself.
Take it or leave it. Just trying to help out.
The LS7 blocks have been no better I hate to tell you.
I know of multiple people that have had to order "more than one" because the machining was so poor from the factory. (I am not saying all of them)
It wouldn't surprise me if the L-92 blocks were no better?
In addition, the people that have told me this are saying this in comparison to LS1/LS6 blocks and LS2 blocks, not C5R and race blocks. It seems the older blocks were made with more precision?
One of the bad blocks was actually part of an LS7 crate engine that was going to be upgraded. I quote: "I thought these engines were hand built?"
It is unfortunate because I actually want to get an LS7 block myself.
I know it is not good news, but I don't think this guy is telling tall tails.
This is just an FYI, I won't be back in this thread to defend myself.
Take it or leave it. Just trying to help out.
#18
Originally Posted by Anonymous
Take it or leave it. Just trying to help out.
#19
Now I can respond to some of the Ignorant posts since I have a life and do not spend hrs a day on the internet. The purpose of this post was to make those who are thinking of purchasing as well as making it known to the brass at GM that there is a major problem with these blocks Considering that these are the same blocks that are getting sent to GM assembly in ST Catherines ,Ontario for the new LS-3 supercharged version of the Corvette.... HMMM would that make it a performance engine... and i guess non of the proud truck owners would care if their engine all of a sudden split a liner just out of warranty!! Trust me i am a die hard Gm owner of 15 corvettes as well as hopped up H2 hummer and Power boats with GM drive lines. The pictures that were taken by the manager at the GM dealer were sent to 5 engineers as well as some top brass that were on a conferance call with him after theblocks were returned. It must have been a concern to someone cause i recieved a call from a test engineer at the assembly plant. If i had the pictures I would deffinitly have shared them. Yes, the one post is correct in that the block consistancy of yesteryear is far infearier to todays casting tolerances, its the precast of the sleeves..or the manual placement before the casting process takes place that is the problem. as for the boring of the mains..yes it done by computer robotics...with MANUAL programming of speed and MANUAL monitoring of condition of cutting tool. The burres could be caused by a dull cutting head..?? It still comes down to GM SELLING ME AN INFERIOR PART..NOT ONCE,NOT TWICE BUT THREE TIMES. And whos to say how many of these blocks were worse then mine and were assembled and placed into vehicles that you or I might buy. Yes i could have the engine shop take a ls-2 block and resleeve it to the desired size but this was a project that we wanted to test as cast from GM.
max
max
#20
TECH Veteran
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Jeez, some of you guys are quick to bash. Are some of you paranoid enough to think that some Ford troll would roll in here and try to bring down the GM performance market by saying a block was junk? I know if I was in the market for a L92 block, that I would want to know of any problems that could surface before hand. That being said, I don't think he's doing anything more than telling the people that purchase these blocks to have them checked over. That being said, i had to return 3 L98 crate motors for busted ring land in the first 25 miles. Once we got one to hold, we sold the car, and the new owner told us the motor went out again after 5k. It's not all that uncommon in the world of GM's mass produced products.