Its not that intakes on many other cars do not add some flow and power but it simply does not on this car. The intake is a better design than any aftermarket or OEM intake in history. It is ridiculously over-engineered with the design of intake flow. A huge lower ram air duct on the bottom drivers side, ram air through the grilles and a hood vent for air escape to keep the velocity moving bringing it cool air and than at higher speeds reversing the use as air intake is drastically needed at high rpms and being able to use that hood vent as a third source of fresh cool air.
Also an elbow does not work different with a paper filter. A paper filter is a true restriction and even that yields only a 5hp gain. Simply put there is a limit to how much air a engine needs and given it is supplied with that its not making more HP with more air.
The filter does not create more power because it flows "more" air, but rather easing the restriction means the engine does less parastic work to draw the air through the filter and thus frees up a few hp. This does not apply with an elbow as there is actualy more work to suck more stagnant, lower velocity air from a larger diameter tube than it does to suck higher velocity air through the smaller OEM diameter.
So really the best combo is the OEM elbow with its higher velocity air moving and a oiled filter to get rid of the work the engine does to suck air in.
This intake is an engineering marvel in itself.