[The Radium King]

i'm pretty sure it's vacuum driven same as on the resonance tube, so i would guess a tee would work. the presence of the flap drives the cost cost of that plenum up over $200 new (vs $48 from suncoast for the 997 unit) but there should be lots of take-offs available used from cayman guys moving to the ipd product. note also that it has two aos connections, so you'll have to plug one or buy a cayman aos line as well. another observation is the hard left turn the air has to make once past the throttle body, vs on a plenum that is more square to the intake.

the 997 plenum is BIG and has very smooth radii. it comes out straight instead of angling off like the original so the old intake pipe can't be reused. note that you have to install it upside down to put the aos connection on the proper side.

i've got a bmc direct air injection (dia) intake that i'm going to use for an airbox, as well as a bmw maf housing coming that i am told is the appropriate size (part # 13621433566 or 0280217533 for those interested, but i can't confirm until i have it in my hands ** edit to add that it was only 74 mm compared to the oem which is 74 mm) and have found a source for flexible, silicone, 3" ducting to connect the throttle body to the maf housing. it should look very professional when done, regardless of what airbox used (oem or aftermarket). note that the bmc universal airboxes come in two sizes - 70 mm and 85 mm; you want the 85 mm otherwise you are introducing a restriction upstream of your 76 mm maf housing.

one thing interesting to note that the plenum/intake runner connections are 3.5" in diameter on each side, so the air expands once it passes through the smaller throttle body. that leads me to believe two things: any intake pulse tuning must happen in the runners themselves and the plenum is just a ready source of air (ie, making it bigger won't reduce low-end power) and anything i can do to get the air to the plenum as efficiently as possible will be of benefit (bigger throttle body, bigger ducting, etc., to the limit set by the maf housing at 3"). this begs dialogue on the next step of intake mods - a larger maf housing. the 3.4 996 engines use a larger maf housing that you could use in conjuntion with the gt3 throttle body, etc., but modifications of the ecu would be required to recalibrate maf readings.