2.25" Catless Downpipe Exhaust for 1990-2001 Acura Integra / 1988-2000 Honda Civic / 1988-1991 CRX / 1993-1997 Del Sol

Free up the exhaust flow on your Honda or Acura and wake up that B-series or D-series engine. The Flashark 2.25" Catless Downpipe replaces the factory catalytic converter section with a straight-through stainless steel pipe — reducing backpressure, sharpening throttle response, and giving your engine a more aggressive exhaust note. Built from 201 stainless steel with a mirror-polished finish, this downpipe comes complete with all hardware for a clean bolt-on installation. No cutting, no welding, no fabrication required. Key Features 2.25" (57mm ID) Pipe — direct upgrade over the restrictive factory cat section Catless Design — eliminates exhaust backpressure for improved flow and throttle response Pre-Welded O2 Bung + Block-Off Plug — supports wideband O2 sensors; plug included if not needed Full Hardware Kit Included — M10 bolts, nuts, washers, donut gasket and flange gasket all in the box Mirror Polished Stainless Steel — corrosion-resistant, built to last Direct Bolt-On Fit — no modification needed, installs with basic hand tools Why Go Catless? The factory catalytic converter is the single biggest flow restriction in the Honda/Acura exhaust system. Swapping it out opens up the path for exhaust gases to exit faster — which means the engine breathes better on every stroke. The result: sharper throttle response, a louder and more aggressive exhaust tone, and a noticeable improvement in high-RPM pull. Whether you're building a street sleeper or a dedicated track car, this is one of the best bang-for-buck upgrades on a B or D-series engine.