the Ultra Series Intake Manifold has undergone extensive in-house dyno and on-car testing which has led to a design that is less restrictive

not just the top end

there are two different sets of holes on the base

Failure to do say may result in potential engine damage:Ô Skunk2 Pro Series Valve Springs (P/N 311-05-5350)

Nissan 350z Z33 3.5 03-06 - Exhaust Y Pipe TESLA the Ultra Series Intake ManifoldOur Nissan 350Z Y Pipe replaces the standard, complex Y pipe with a single piece, 2. 25" bore T304 stainless steel item. It also includes a pair of flexi joints to help reduce noise resonance without sacrificing performance. Features: Manufactured from T304 stainless steel 58mm 60mm Bore Includes two flexi joints Mirror polished finish Fits: Nissan 350Z Z33 3. 5 2003 2006 models