What is the difference between corrected and non-corrected torque ratings i've seen on the dyno

Corrected numbers are for comparisons between different atmospheric conditions. Cool air makes more power. So a run first thing in the morning at say 50 degrees outside air temp will tend to look better than the identical run in the afternoon at say 75 degrees air temp. Or if you trying to compare a run in Denver Colorado at 5,000 feet altitude with one in Los Angeles at sea level. Air gets thinner and makes less power as the altitude increases. It gets a whole lot more complicated but that is the short story.