True....and intake air temperature is very important, even more so with a turbo. The intercooler can only remove so much heat before sending it to the manifold. If the intake air is preheated by the engine compartment, to say 200F, that's a huge heat load for the intercooler and a big drag...you're not getting as much oxygen into the cylinders. By contrast, if the intake air is 100F (or whatever outside ambient temperature is) you could potentially be getting 2x as much oxygen into the cylinders and firing the engine with more optimal mixture....that means more power. Throttle response and lag might be improved a little...with an underhood intake...but at the sacrifice of power and efficiency.The Better you can Get air in and air out the better the performance.
I have the 2016 Buick Regal, I used the 2013 Chevy malibu 2.0t Injen and it fit up just perfect like it was made for the Buick