OVERVIEW

Downpipes are a proven modification on the N54, and Speed Logic's catless race downpipes for the 135i and 335i are good for over 30 wheel horsepower and 40 lb-ft at the wheels with adequate tuning. They use a full 3" one-piece cast section at the V-band connection to the turbos, which keeps flow smooth and turbulence low where the factory pipe is at its most restrictive, and the improved flow brings a noticeably deeper engine and exhaust tone. Construction is 304 grade stainless throughout, TIG welded and argon backpurged, and every set ships with the gaskets and Grade 10 bolts, washers and nuts needed to complete the installation. All Speed Logic products carry a lifetime warranty against manufacturer defects and fitment issues.

SPECS

Full 3" diameter, one-piece cast design at the turbo V-band entry, stepping to a 2.5" connection at the midpipe / catback
Catless race downpipes - one for the front turbo, one for the rear turbo
Full 304 grade stainless steel construction
Adds 30+ horsepower and 40+ lb-ft of torque with adequate tuning
100% TIG welded, all welds fully backpurged with 100% argon
Welds are not ground or polished
Works with all stock-location turbos: OEM, Pure Turbos (Pure600, Daily Driver, High Flow), Vargas Turbos (Stage 1, Stage 2, Stage 2+), RB Turbos (Stage 1, Stage 2, Stage 2+, GFs)
Replaces OEM BMW downpipe part numbers 18307587609 and 18307587610
Gasket set and Grade 10 downpipe hardware included
Fits both Left Hand Drive (LHD) and Right Hand Drive (RHD) vehicles without modification
Catless - off-road use only, not available for sale in California or other emissions-testing states
Includes a Speed Logic LIFETIME warranty against defects and fitment issues

PARTS INCLUDED

(2) Speed Logic downpipes - one for the front turbo, one for the rear turbo
(2) Downpipe gaskets
(4) Bolts, washers, lock washers and nuts for the midpipe connection

TECH RESOURCES

Additional Parts Required

A tune is required. These are catless downpipes, and without supporting software the car will log catalyst efficiency faults and throw a check engine light. Speed Logic supplies the MHD Super License for N54 Engine and the JB4 Tuner for N54 BMW.
No other hardware is needed - the gaskets and Grade 10 fasteners for the midpipe connection are supplied in the box.

Installation

No installation document is published for these downpipes. Our team is available to answer fitment questions, and installation is available at our Southern California facility.

Notes

*NOTE: Speed Logic Downpipes are for OFFROAD USE ONLY and not available for sale in California and other states with emissions testing.
Speed Logic does not publish its own part number for these downpipes, so no part number is listed - the OEM numbers they replace are shown in SPECS. This part is sold for off-road and competition use only.

VEHICLE APPLICATIONS

Make	Model	Chassis	Engine	Years
BMW	135i	E82 / E88	N54 3.0L Twin-Turbo I6	2008-2010
BMW	1M	E82	N54 3.0L Twin-Turbo I6	2011
BMW	335i	E90 / E91 / E92 / E93	N54 3.0L Twin-Turbo I6	2007-2013
BMW	335is	E92 / E93	N54 3.0L Twin-Turbo I6	2011-2013