I ran up on a motor today at that had some different numbers than I am use to seeing. The block is aluminum with 6.0L cast into the back. The heads have 823 as the part number and are also aluminum and the intake ports look different than the LS1/LS2(more square shape).Would this motor be the L76 or what? If somebody can tell me what it is and if they are a good starting point to build off of I would appreciate it. Thanks

 

Sounds like it's an LS2 block with L92 heads. That's a great starting point for a build.
L92 head info, with casting No 823 highlighted.
https://ls1tech.com/forums/showthrea...&highlight=823

If it was a Vortec (truck) L76 it would have a VVT cam phaser hanging off the front of the cam.



If it was a car L76 (not likely) it wouldn't have VVT but instead would have a Lifter Oil Manifold Assembly in the valley.


Both versions of the L76 have tiny cams.eg: about 200/208 0.472 0.479