[DaSkinnyGuy]

From what I understand LS1 engines made before April 2001 had a different piston and ring set ( I hear the slap on my 2000 LS1), its normal to hear the piston slap until the engine warms up. You may also have another problem, just like sweetbmxrider has mentioned, use a screwdriver and or stephoscope to listen around the valve cover area, exhaust manifold area,could be an exhaust leak, egr leak, pulley going bad, ac compressor the work computer doesnt have good audio hard to tell from the video. Also LS1 engines made before april 2001 its normal for oil consumption, caused by ring flutter because they used the wrong ring package.