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Evolution Racewerks - Competition Series 4.5" Catless Downpipe - BMW F30 340i (B58)




Restrictions in the exhaust system robs horsepower and torque especially on turbocharged cars. Thus, removing as much exhaust flow restrictions will increase horsepower and torque significantly. The factory catalytic converter found in the factory downpipe is a big culprit of this and is a major exhaust flow restriction. The factory catalytic converter is made up of catalyst material formed into "honeycomb" weaves. Exhaust gas must pass through these tiny "honeycomb" weaves on their way to the exhaust system thus causing a major exhaust flow restriction. It also causes turbulence after the catalytic converter which causes the exhaust flow to slow down (which increases restriction). By replacing the factory downpipe/catalytic converter with our Competition Series 4.5" Catless Downpipe, more power is unleashed! You will feel the difference instantly. 

The new turbochargers on the B58 engines utilize a much larger 4.5" outlet compared to the 4" outlet on the older N55 engines. If Evolution Racewerks ran a 4" downpipe flange inlet so that they can use 4" tubing, a "step" would be formed between the turbocharger outlet and downpipe inlet. Exhaust gas for the turbocharger would hit this "step" and a lot of turbulence would form at this point and cause backpressure. Backpressure this close to the turbocharger would greatly affect performance. Thus, to ensure that you get unobstructed flow from the turbocharger outlet to the downpipe inlet, Evolution Racewerks had to CNC machine a new 4.5" flange to match, which allows a seamless transition and eliminate any possible turbulence which would cause backpressure.

- Fitment for the new BMW B58 Engine
- Higher Max Horsepower Power Curve
- Higher Intial Torque Curve. Torque curve hits faster and higher and longer.
- Better throttle response and faster turbo spool up times.
- Mandrel Bent 4.5" piping. Smooth transition to the exhaust system.
- 100% Stainless Steel Construction
- 100% TIG welded for better quality welds
- Precision CNC machined turbocharger V-Band flange.
- Brush Finish (standard) or optional Polish Finish
- Available with high temperature Black Thermal Coating to reduce underhood temperatures.
- Optional - Additional O2 sensor bung for wideband O2 sensors (comes with pre-installed plug)
- Optional EGT sensor bung for EGT gauges (comes with pre-installed plug)
- Compatible with the factory or aftermarket exhaust systems.
- Track tested durability.
- Includes all hardware for complete installation.
- Limited Lifetime Warranty.

Optional Ceramic Thermal Coating
The purpose of ceramic coating downpipes is to keep heat from the exhaust gases inside the downpipe from radiating out. This keeps underhood temperatures lower and less heat absortion by nearby parts/surfaces. Another added benefit is that by keeping in heat (energy) in the exhaust gases inside the downpipe, exhaust flow velocities stay up, resulting in lower backpressure. The ceramic coating also adds additonal corrosion resistance. We utilize the best ceramic coating possible. Our thermal coating can resist up to 2000F of heat.

Optional Additional O2 Sensor Bung
An additional O2 sensor bung can be added so that you can easily add a wideband o2 sensor and gauges so that you can monitor air/fuel ratios. The additional O2 sensor bung will come pre-installed with a plug so that you do not need to run the o2 sensor right away.

Optional EGT (Exhaust Gas Temperature) Bung
An additional 1/8" NPT bung can be added so that you can easily add a EGT sensor and gauge. The optional EGT sensor bung will come pre-installed with a plug so that you do not need to run the EGT sensor right away.

Models Supported:
BMW F30 340i

WARNING: May contain items that are found to have compounds and/or chemicals known to the State of California to cause cancer, birth defects, and reproductive harm.
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