2012-UP BMW N55 F30 F32 F33 F20 F21 Turbo Competition Series 4" Catless Downpipe

BM-EXH007 / BM-EXH012

Competition Series 4" Downpipes for your 2012+ 335i (F30 Chassis) six cylinder N55 turbo engine, 2013+ 435i (F32/F33 Chassis) six cylinder N55 turbo engine and 2012+ M135i (F20/F21 Chassis) six cylinder N55 turbo engine

Between 2013-2014 BMW changed the downpipe features.
Please read below important notes:

The F Series (1,2,3,4 Series) N55 cars all share the same downpipe.  When first introduced, the downpipes had a 3.5" v-band flange intlet on the turbocharger side.  On 07/13, BMW decided to change the downpipe.  This new downpipe featured a 4" v-band flange inlet instead.  Thus, the previous downpipes are not compatible with the new ones. 

Below is the breakdown on which downpipe to chose based on production date:

335i (U.S. Spec) - Up to 07/13 have the old downpipe (BM-EXH007)

                          After 07/13 have the new downpipe (BM-EXH012)

435i (U.S. Spec) - All 435i have the new downpipe (BM-EXH012)

M235i (U.S. Spec) - All M235i have the new downpipe (BM-EXH012)

M135i (European Spec) - Up to 07/13 have the old downpipe (BM-EXH007)

                                   After 07/13 have the new downpipe (BM-EXH-012)

IF THE VEHICLE IN QUESTION IS BUILT ON 07/13, IT CAN HAVE EITHER DOWNPIPE.  A VIN# CHECK SHOULD VERIFY WHICH DOWNPIPE IT IS.  TO BE ABSOLUTELY SURE, A VISUAL INSPECTION NEEDS TO BE DONE.  SINCE THE FACTORY PART# ON THE DOWNPIPES ARE DIFFICULT TO SEE, THE BEST WAY TO CHECK IS TO LOOK AT THE PART# ON THE BRACKET HOLDING THE DOWNPIPE.  THE OLDER DOWNPIPES HAVE 2 STUDS GOING INTO THE BRACKET AND ATTACHED BY 2 NUTS.  THE NEWER DOWNPIPE HAS 1 STUD ON TOP ATTACHED BY A NUT.  THE BOTTOM BRACKET IS ATTACHED WITH A BOLT, NOT A NUT.

SHOWN WITH BRUSH FINISH
 

CAUTION: This product is intended for OFF ROAD COMPETITION USE ONLY. Not legal for use on pollution controlled vehicles upon public road/highways. THIS PRODUCT IS FOR SALE FOR ALL 49 STATES EXCLUDING CALIFORNIA.  In addition to vehicle use verification, a Vehicle Compliance Waiver needs to be signed.

THIS ITEM IS NOT FOR SALE, INSTALLATION, OR USE ON LICENSED VEHILES IN THE STATE OF CALIFORNIA. 

The item is for sale for international customers without restriction.

Key Features:

• Available for the 2012+ BMW 335i (F30 Chassis) N55 Engines!
• Available for the 2013+ BMW 435i (F32/F33 Chassis) N55 Engines!
• Available for the 2012+ BMW M135i (F20/F21 Chassis) N55 Engine!
• Better throttle response and faster turbo spool up times.
• Mandrel Bent 4" 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.

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" Catless Downpipe, more power is unleashed! You will feel the difference instantly.

Shown in brushed finish


Our Competition Series Catless Downpipes is constructed out of 100% 304 grade stainless steel and utilize mandrel bent piping.  They are 100% TIG welded by our in house fabricators and built in the USA.  The factory turbocharger turbine housing utilizes a V-Band flange which we have duplicated and CNC machined cut out of billet 304 stainless steel.  Stainless Steel CNC machined O2 sensor and laser cut brackets are TIG welded using stainless steel rods.  The O2 sensor is positioned at the factory location.  Since the outlet of the turbocharger is 3.5" and the factory exhaust system is 3", the factory downpipes reduces size using short transitions from 3.5" before the catalytic convert and 3" afterwards.  Due to space needed for the cataylic converter, the factory downpipes reduce in size using very short transitions.  Since our catless downpipes delete the cataylic converter, we have more space.  Thus, we use very long transitions.  These longer transitions allow the exhaust gas time to smoothly transition from the larger piping to the smaller.  Also, since we utilize a larger 4" pipe right after the turbocharger, turbo backpressure is significantly reduced.  This results in less exhaust turbulence and backpressure which again improves throttle response and increase turbocharger spool times (less turbocharger lag).

 

CNC Machined Billet Stainless Steel V-band Flange


Our downpipes are designed to fit perfectly with either the factory exhaust system or your aftermarket exhaust system.  There are no compatibility issues whatsover.  The downpipes will come by default in Brushed Finish.  We also offer a Polished Finish as an option.