Evolution Racewerks Sport Series 4" Catted Downpipe – BMW 320i / 328i / 420i / 428i (N26)

OVERVIEW

Evolution Racewerks' Sports Series 4" High Flow Catted Downpipe for the N26 engine fits all 2012 and newer 320i, 328i, 420i and 428i models equipped with that engine. It does not fit the N20 engine.

The factory catalyzer uses a 400 cell ceramic core, meaning exhaust gas must pass through 400 cells per square inch. Evolution Racewerks uses a 200 cell metallic core: fewer cells per square inch means each cell is larger and exhaust passes through more easily, so flow goes up. Higher flow means more power, faster turbo spool and better throttle response. A metallic core also handles more heat, lasts longer and weighs less than the ceramic factory unit. Because exhaust restriction robs horsepower and torque on turbocharged cars, replacing the restrictive factory downpipe and converter unlocks meaningful power.

The downpipe is built from 100% 304 grade stainless steel with mandrel bent piping, 100% TIG welded in house and made in the USA. The 4" turbocharger V-band flange is CNC machined from billet 304 stainless steel, and the O2 sensor stays in the factory location. The headline feature of the N26 version is its CNC machined solid stainless steel billet ball joint. BMW press-forms its ball joint, which mirrors the shape on the inside of the pipe, so exhaust dives into the valley and back out again and creates significant turbulence right at that point — turbulence that slows exhaust velocity and raises backpressure. ER machined the ball joint from solid billet instead, keeping the factory connection while leaving the interior smooth so exhaust flows through unrestricted. ER's in-house testing showed real world improvements from the billet joint, which is why the N26 downpipe costs more than the N20 version, where a simpler slip-fit design is used.

Like the factory downpipe, the ER piece incorporates a 100% stainless steel flex section so the exhaust system can move without loading the turbocharger, exhaust manifold and other components. Competitors often delete this; over time a rigid system accelerates wear and cracking, and it cannot deflect impacts on a lowered car.

SPECS

• Catalytic converter: high flow 200 cell metallic core
• Piping: mandrel bent 4", with long transitions down to the 2.5" factory exhaust diameter
• Construction: 100% 304 grade stainless steel, 100% TIG welded, built in the USA
• Turbocharger flange: precision CNC machined 4" V-band cut from billet 304 stainless steel
• CNC machined solid stainless steel billet "ball" joint reproducing the factory exhaust connection with a smooth interior
• 100% stainless steel flex section, as used on the factory downpipe
• O2 sensor retained in the factory location; CNC machined O2 bung and laser cut brackets TIG welded with stainless rod
• Finish: brushed as standard, mirror polish available
• Optional high temperature black thermal coating to reduce underhood temperatures
• Optional additional O2 sensor bung for a wideband O2 sensor, supplied with a pre-installed plug
• Optional EGT sensor bung for EGT gauges, supplied with a pre-installed plug
• Compatible with the factory or aftermarket exhaust systems
• Track tested durability
• All hardware for a complete installation is included
• Warranty: Evolution Racewerks Limited Lifetime Warranty

PARTS INCLUDED

• Sports Series 4" high flow 200 cell metallic catted downpipe with billet stainless ball joint
• All hardware required for complete installation, as supplied by Evolution Racewerks

TECH RESOURCES

Additional Parts Required

• None. Evolution Racewerks specifies no additional hardware for this part; all installation hardware is supplied and the downpipe mates to the factory or an aftermarket exhaust.
• A signed Vehicle Compliance Waiver and vehicle use verification are required before this part can be sold and shipped.

Installation

• Evolution Racewerks does not publish a downloadable installation guide for this downpipe. It bolts to the factory turbocharger V-band flange and connects to the exhaust through the reproduced factory ball joint.
• Verify whether your car has the N26 or N20 engine before ordering — this downpipe fits N26 only. Contact Speed Logic if you need help confirming your engine.

Notes

• Does not fit the N20 engine. Fitment above follows Evolution Racewerks' published application data; confirm your chassis and engine code with Speed Logic before ordering.

PART NUMBER

• BM-EXH010SCAT — Evolution Racewerks catalog number for the N26 Sports Series 4" high flow catted downpipe
• Store variant numbers: BM-EXH010CAT (brushed), BM-EXH010CAT-Polished, BM-EXH010CAT-BLK (black thermal coating)

VEHICLE APPLICATIONS