[RalphP]

Let's keep one thing firmly in mind.

The factory box? Is a CAI already (notice where it sucks the air from.)

Most CAIs? Are actually WAIs, and suck less dense warm under-hood air.

Why doesn't this show up on bench dynos? Because either way, you have cool air around the filter. Try checking on a rear wheel dyno during a hot day with the engine bay heatsoaked some day ...

Besides, only rarely is the intake at this point the choke point for the motor.

I WILL say that removing input noise silencers can yield some nice sound effects *grins* Also, it does pay to find a nice low-restriction air filter (I'm partial to Wix myself).

RwP

 

[RalphP]

Technically sure.

Practically however there can be over 25 DegC difference between ambient air temperature and the air temperature at the intake manifold where the air temperature sensor is.
I know, I've measured it in real time while driving on a 2006 4.7 Dakota.
The problem is that the factory system allows the air stay inside the ducting longer allowing it to heat up. In effect its running as a heat exchanger as all these systems will, but its got a more efficiency at transferring that heat to the intake air.

Which - said effect is minimal to non-existent when the motor is running at WOT. Or you're cruising down the road.

And *ahem* if you stick the air filter INSIDE the engine bay, you can't AVOID that hot air off the motor.

Makes more sense to better insulate the plumbing inside, if that's a concern to you.

But eh.

RwP