BMW introduced a new valvetronic, single turbo version of its direct-injection engine for the F-Chassis models beginning in 2012. The Active Autowerke N55 downpipe for the M235i, 335i, 435i and M2 helps unleash some of the potential that is restricted by the OEM downpipe.

Turbochargers are powered by spent exhaust gases created during the combustion process. The quicker these gases are evacuated, the better. Unfortunately, the factory down pipe in the N55 is quite restrictive, which results in slower exhaust gases and slower turbo spool.

The Active Autowerke F-Chassis N55 Signature down pipe utilizes 3.5” diameter stainless steel piping in order to provide more power, quicker spool, and extreme durability. This variant includes a 4.5" high flow GESI catalytic converter that will NOT produce a CEL!

The GESi® G-Sport Ultra High Output Catalytic Converter features full 304 stainless steel construction, including the substrate. GESi® UHO-Series Catalytic Converters are EPA certified in 49 states and fully OBD2 compliant. GESi® proprietary precious metal loading technology ensures greatly reduced emissions, eliminating most "Check Engine Lights". These high flow catalytic converters outperform stock converters and provide a reliable solution to the most common catalytic converter problems.

The GESi® UHO-Series Catalytic Converters are rated for engines putting out between 500 and 850 horsepower while maintaining a high flow capacity. The reduced back-pressure from this high flow catalytic converter will allow you to maximize your engines horsepower without the harmful emissions. Say goodbye to Check Engine Lights and failed emissions tests!

Please Note: These catalytic converters are not legal for use on vehicles registered in the state of California as a result of California Vehicle Code Section 27156 and 38391.

• NO CEL when using this downpipe
• Designed to be as unrestrictive as possible
• GESI EPA registered high flow and fully OBD2 compliant
• High flow 4.50" GESI cat with 3.50" piping allows for maximum power output
• Quicker turbo spool - improved power over stock
• Rated for 500 to 850 hp applications
• Withstands up to 1500° F
• Can reach operational efficiency within 9 seconds of startup
• Easily bolts-on – no cutting or welding required
• Durable construction from TIG welded 304 stainless steel
• Precise fitment
• Modular design for later upgrades
• Made in Miami, Florida
• Ultra high flow 400 cell per square inch catalyst
• EPA certified for use on OBD2 vehicles (1996 and newer) except in California
• Full 304 stainless steel construction
• 304 stainless steel substrate in the catalytic converter is furnace braised to the mantle for outstanding durability
• GESi® proprietary precious metal loading technology ensures greatly reduced emissions
• Ideal for Forced Induction Applications with no loss of HP
• Both passengers and drivers are safe from harmful emissions and noise

Signature Benefits

The speed of a turbo’s impeller wheel is limited by exhaust back pressure. A larger down pipe relieves some of this pressure, resulting in quicker and more efficient spool. With Active Autowerke’s Signature downpipe, your N55 can rev quicker, and deliver more horsepower and torque.

Minimizing back pressure while remaining daily drive-ability was the goal of our N55 downpipe. Owners can now upgrade to a product that is affordable, reliable, and easy to install. 

After months of research and development, our engineers settled on a 3.5” diameter pipe which utilizes the least number of bends possible. However, the Signature N55 down pipe still fits easily into the OEM location, with a painless installation process.

Constructed entirely from 304 stainless steel with 1.5MM wall thickness, we are confident that you’ll be pleased with how robust and durable this down pipe is. Trouble-free installation and a long lifespan ensure that you’ll enjoy many miles of performance with your N55!

BMW N55 Engine

11-040

Warranty

Covered by 5 Year / 50,000 Mile Warranty (on catalytic converter)