I just pulled the oil pan off... I knew this LS1 was modded when I bought it, but had no idea...
It's a STROKER!!!!!! 
Eagle H-beam rods, ARP studded mains, ARP rod bolts, and some nice little notches on the bottom of the cylinder wall, along with the windage tray being shimmed indicative of a longer stroke.
Seriously, when I bought it on ebay, the only "mods" that I knew about was headers (which won't fit my car anyway) and an SLP MAF sensor. When the guy pulled it, he called to tell me the heads were studded. Jeff (piette) picked it up for me, and he started looking it over, and noticed the LS6 intake and Ford injectors. I still don't know what cam is in it, but I should have that figured out this week.
