E90 335i N54 Decat Downpipe & Cat-Back Exhaust System, Dinan Part #102117

Dinan 102117 is a full decat downpipe and cat-back system for E90 335i (N54) - not a resonated mid-pipe or 'decat-style' fake-out. It’s what you fit before stage 2, or run solo on a fast road or track day build where emissions compliance isn’t the priority.

• Direct bolt-on to stock turbo outlet - no spacers, no flange mods, no guesswork
• Stainless steel throughout: 3-inch mandrel-bent downpipe + 2.75-inch cat-back with twin 3.5-inch black tips
• Removes both pre-cat and main catalytic converters - expect check engine light unless paired with appropriate tune
• Fits E90/E91/E92/E93 335i N54 only (2007-2010); not compatible with N55 or xDrive variants
• Search terms covered: E90 N54 decat, 335i stage 2 exhaust, N54 full decat downpipe, E92 335i track day exhaust, BMW 335i fast road exhaust, E90 335i cat-back no cats

Because race car.