There is probably an "air box" that has been removed to show off the velocity stacks. This would mount to the end of the hose. This type of set-up is actually very similar to the "throw-back" individual carbs. of old. I was running 40 mm DCOE Weber side drafts years ago on my BMW. As mentioned above the "balancing" of the air flow must be done by an experienced shop. In the current case, I'm not sure how much would really be gained over a high flow intake with a larger throttle body...besides the bling factor!!

 

Yeah I think the snorkle and pipe is just there to draw more cold air towards the ITBs.

I've heard that ITBs give you another 20-30whp, for about $6000.

 

Yes, I think that's correct, but I'm not sure. I suspect that air is fed through the CAI into a box which contains the pipes. Intake air is drawn through the pipes. And, yes, either a filter goes in the box, or one is available for the tip of each pipe.

OTOH, I agree that this setup without a box would still provide for more air under the hood to be drawn into the pipes. The far pipe, though might be starved for air a bit though without a containing box.