2SO2 + O2 >>>> 2SO3

delts h = -197.8 KJ

K= 0.0114 at 400 degree Celsius

engineers have found that SO3 can be produced faster by increasing the temperature to 400 degree Celsius, even though this change favors the reverse reaction. suggest an explanation

Keq doesn't say anything about how fast the reaction will occur. Higher T means molecules with more energy which will allow them to overcome any energy barriers.