The Gen III LS1 engine factory-installed in '98-'02 Firebirds, '04 GTOs and the Gen IV LS2 between the fenders of the '05-'06 GTOs are excellent powerplants. - High Performance Pontiac Magazine ...

LS1 Power Plan Part II Inlet-air temperature 77.1 degrees F, barometric pressure 29.72, vapor pressure 0.15 inch HG, correction factor 0.99.