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A big motor making big power at low boost levels needs a big pair of wastegates as sometimes more than half of the total exhaust volume can be dumped through them. Dual 50mm Turbosmart Pro Gates handle boost regulation activities. The Pro Gates were selected for both their high flow and compact footprint. As you can probably guess, space is at a premium under the hood of the BRZ and the small low profile Pro Gates allow close to ideal wastegate position while still packaging in the tight confines under the hood. Bigger wastegates would require the exhaust layout and wastgate position to be compromised. The discharge tube of the wastegates are a huge 2.5″ in diameter, bigger than most cars exhausts. At night you can see flames from the wastegates discharge tubes that poke through the hood.
Turbosmart Race Port blow off valves were also selected for their high flow and compact, low profile size that allowed for close to ideal positioning close to the throttle body.
A Wilson Performance billet intake manifold withstands boost pressure and has a large plenum to support the flow demands of the huge 8 liter engine. Injector Dynamics 2000cc fuel injectors handle the feeding of the engine. Wilson Performance fuel rails are used.
JSP's John Russakoff constructed the custom turbo headers from 321 stainless steel provided by Burns Stainless. The headers are stepped and have 2.25″ primary tubes feeding into Burns Stainless superb merged short collectors. Burns also supplied the stainless bellows and V-Band clamps. The collectors feed into 3″ transfer tubes that feed either side of the Garrett GTX50R twin scroll exhaust housing. It's too bad that the heat insulation hides all of John's beautiful work. 
Heavy duty LS7/Truck coils are used. They are heat sensitive so a lot of shielding is required. If you have stock in a thermal wrap company, this car contributed to your bottom line!
The huge air to air intercooler uses a Garrett bar and plate core with the tanks designed and fabricated by Scott Dodgion of SPD. The tanks were sculpted as much as possible for good air flow within the tight space constraints of the front of the car. 
