Reason for 4 intake resonators?
 

Recently it has come to my attention that the FR-S/BRZ has 4 intake resonators. I wanted to ask the community for insight into why there are 4. Two are larger bottle like shapes and 2 are small branch resonators, one of the larger ones appears to be on the engine side of the MAF. Do you guys think these are simply for noise control or do they play a role in tuning the intake pressure waves or is it something else. ?

Perhaps this car was designed by committee (:iono:).

Errr... both?

There is some fancy acoustic (pressure wave) tuning involved to get the big boost of torque they manage at the low rpm hump and still pull decently up top. If you look at Perrin's dyno that got them the 4 lb-ft gains up top, you can see they lost about the same or more at the low hump.

I think there's a good market opportunity for a company to come out with a set of caps to replace all the resonators and the sound generator... I'd buy it.

If you keep it NA: stay with the stock intake / airbox

If you go FI: fit a CAI with a bigger filter unit