I will admit, that when we pulled the first motor out of the 2002 ZL1's, and the casting number was the exact same casting number that I was putting back in the car, I was a little confused. So, I called the GM engineers we were working with and asked them how could a 2002 Camaro come with an LS6 motor. They said that the piston knock and oiling problems prompted GM to update the block. When GM updates parts, like an engine block or cylinder heads, they will almost always change the casting number, to signify a change or update has been made to the previous part number. So, if there are different casting numbers for an LS1 block, you can be sure there is something different about the blocks. The engineer also went on to say that they started filtering in the LS6 casting number blocks in Camaros and Firebirds in 2001 because of the continued piston knock problem. He said that about 20% of the 2001 f-bodies will have the LS6 casting number and about 70% of the 2002 f-bodies will have the LS6 casting number. We found 3 different casting numbers on the 69 motors we pulled out, but most of them were the LS6 casting numbers. To the extreme novice, again CAMAROSSS that would be you here, the motors seem to be the same, but if you had a production LS1 out of a 2002 CAMARO and one of the LS6 crate motors we bought from GM, you could probably find 15 things between the two of them that are different. The idea was brought up to me a long time ago, about how I could have saved a lot of money by just changing the heads, and cam and leaving the LS6 casting numbered motors in the cars, but I explained to them about the 15 differences and they agreed with me that it would have been obvious that we frauded people, if we did that. The first big give away that your block is a factory block is the VIN number like Ron said, and he would know since he helped build all of these cars. The second biggest way to see if your block is an LS1 or LS6 casting number is on the front of the block below the throttle body, there are obvious casting differences. I'm sure this topic has come up here so I wont go into it, but I would recommend that CAMAROSSS does look it up, and next time you speak as if you know the truth about something, just remember, someone will always know more about it than you. I heard someone say, God created us with two ears and one mouth, and we should listen twice as much as we speak, that's something you should think about. This issue of GM using the same casting number for both LS1 and LS6 engines, is going to continue to cause problems for many years. Remember, always do your homework and research it before you think you know what you're talking about, because you might find out that there is a simple answer for why you were wrong. I'll bet many people including CAMAROSSS didn't know that GM Parts actually made a seperate part number and LS6 motor combination for the ZL1 project. In 2002, all you could get was a complete LS6 warranty block with all the Corvette accessories. The price was over $11K, which would have made the project too expensive if we had to pay that much for those motors. One of the many things GM helped us with on the ZL1 project was the engine cost. They came up with a new GM Part number and created a LS6 motor package made for the Camaro, without the Corvette parts and LS6 intake, and saved us over $6K per motor. That LS6 crate motor and part number is pictured in the GM Performance Parts catalog.

So, I called the GM engineers we were working with and asked them how could a 2002 Camaro come with an LS6 motor. They said that the piston knock and oiling problems prompted GM to update the block.