Colder the air, the denser it is and hence greater oxygen content. So that’s all to the good. BUT, air box design is a bit more of a science than merely having as big a hole as possible. Boxes are designed by a combination of shape, volume and intake hole to achieve an optimum air flow at a resonant frequency designed to be at a point where torque might otherwise drop off due to engine characteristics. (Helmholtz Resonance principle) So, don’t throw away the bits you’ve drilled out, you may wish to stick them back on!
I fully agree to your point! But in case of the pics of the original airbox of the 3.7 Roadster shown above the input opening doesn't look really professional and calculated, but rather like someone sawed out a piece where there happened to be some space left. Of course I could be wrong about that, I also believe that the disappointment is great when the resonance of the airbox is no longer right. You'll notice that e.g. when at low revs this acute impact is missing and the acceleration feels weak and without initial torque but also at higher revs something could just feel wrong.
Because of that I have kept the airbox of my 4/4, a first trial without it gave worse results even if the way to the TB was shorter.
I have just as much respect for the engineers' airbox calculations as I have for a well tuned bass reflex speaker. (even if the air is flowing in the airbox and only vibrates in the bass reflex box).
