Like any engine factory, they have suppliers or another division produce the parts to within certain tolerances. It is well known that there is slight deviation in parts. For example, in Spec Miata racing, the top guys buy multiple motors from the factory and tear down the motors and measure every part and put the best parts back together from all the motors to get a 'spec' motor that is 10% higher HP than the avg motor. I guess this is possible to happen 'accidentally' by random selection of parts from a bin, but I doubt it. Then again, sometimes you get a high number posted on here that is just a fluke without explanation.