BMW 335i N55 E90 / E91 / E92 / E93: straight-six, single turbo, the exhaust system guide

The N55: BMW's inline-six switches to a single turbo

The N55 retains what makes a BMW inline-six so appealing: natural balance, great smoothness and a real eagerness to rev. Its 3.0 litres are fed by a single twin-scroll turbo, combined with direct injection and Valvetronic valve control. It produces 306 hp and 400 Nm, with torque available very early that makes every burst of acceleration easy.

On this engine, the turbo already absorbs a good part of the noise, and the factory exhaust does the rest: the six-cylinder is sensed more than heard. The Rog valved exhaust replaces it without modifying the engine or its map, and gives the N55 back the smooth, drawn-out sound that made Munich's six-cylinders famous, while letting you return to calm whenever you wish.

How the exhaust on your BMW 335i N55 E90 / E91 / E92 / E93 is put together

An exhaust system is best understood in two parts. Here is what each one does, and what Rog replaces.

Your BMW 335i N55 E90 / E91 / E92 / E93 in figures

On a modern car, an exhaust system first changes the voice, the breathing and the weight at the rear. Power, on the other hand, comes from an ECU remap.

Published factory and Stage 2 figures.

Our exhaust systems work perfectly with or without an ECU remap. On your BMW 335i N55 E90 / E91 / E92 / E93, however, we recommend one at an approved tuning centre: it is what lets the engine deliver its full potential.

The N55 takes tuning well: its design leaves headroom that a Stage 2 remap knows how to exploit, particularly in terms of torque. Nothing is automatic, however: the condition of the engine, its maintenance and the tuner's work determine the result. In this context, the Rog exhaust is the logical complement to the project.

Configuring your exhaust, step by step

4 choices, in the same order as the product page configurator.

1. 1

   Step 1 of 4: Material: stainless steel or titanium

   Titanium costs more than stainless steel; the price of each version is shown on the product page, in your currency.

   304 stainless steel

   Weight

   Baseline

   Sound

   Full and rounded

   The benchmark for high-end exhausts: tough, corrosion-proof, with a full, rounded sound. The choice of most of our customers.

   Titanium

   Weight

   Around 40% lighter

   Sound

   Metallic, crystal-clear

   Around 40% lighter than stainless steel for the same design, with a more metallic sound that turns crystal-clear at high revs. Its finish ranges from brushed to blued tints.

   Over time, both hold up: 304 stainless steel stands up to winter salt and damp, and titanium does not rust. Stainless steel or titanium: what really changes.

2. 2

   Step 2 of 4: Front section: downpipe and catalytic converter

   Optional: the downpipe on your BMW 335i N55 E90 / E91 / E92 / E93, with its catalytic converter. Sound intensity is rated on our scale of 0 to 10, valves open; the factory exhaust scores 3.

   Cat-back only

   Included

   7/10

   Factory emissions control

   The factory catalytic converter stays in place. The starting point and, for many of our customers, more than enough.

   200-cell sports catalytic converter

   8/10

   Road use and inspection

   Emissions control is still very much there, and flow improves noticeably. The choice for everyday driving.

   100-cell sports catalytic converter

   9/10

   Inspection: depends on local rules

   Half as many cells: flow comes close to a decat and the sound gains real aggression at high revs.

   Decat

   10/10

   Track use

   No emissions control: maximum flow, raw sound, the sharpest revving.

   Sound intensity, on a scale of 0 to 10

   1. 10/10Decat downpipe + Rog cat-back
   2. 9/10100-cell sports catalytic converter + Rog cat-back
   3. 8/10200-cell sports catalytic converter + Rog cat-back
   4. 7/10Rog cat-back only, factory catalytic converter retained
   5. 3/10Factory exhaust, for comparison

   Valves open. With the valves closed, every configuration becomes discreet again.

   What about the engine warning light? With a sports cat, it can come on with some engines: the sensor placed after the catalytic converter measures a different level of emissions control from the original. It is not a mechanical failure, but a warning light should never be masked or cleared without dealing with its cause: the right answer is a catalytic converter suited to the engine, with a map by a tuner who takes it into account. The decat version, for track use only, almost always triggers it. If this happens to you, write to us and we will point you in the right direction. Passing vehicle inspection with a sports exhaust.

3. 3

   Step 3 of 4: Valves: Rog remote or factory control

   Two ways to control the valves on your BMW 335i N55 E90 / E91 / E92 / E93.

   Rog remote

   

   A small control unit fits in the trunk. Two buttons, open and closed: the valves respond at any moment, whatever the drive mode. Simple to fit, and we stay on hand throughout the installation.

   Factory control

   • Only for vehicles fitted with factory valves
   • Controlled by the drive modes

   If your vehicle is fitted with factory valves, the exhaust keeps their existing control. The drive modes decide, just as they did from the factory, with no added electronics.

   On the highway, with the valves closed, the gases pass through the muffler, designed for cruising: no drone at a steady speed. You open up when you feel like it, not when the highway decides for you. More about exhaust drone.

4. 4

   Step 4 of 4: Tips: the visual signature

   Match the tips to the style of your BMW 335i N55 E90 / E91 / E92 / E93, understated or bold. A particular finish in mind? Send us a photo and we will look at it together.

   • Stainless steel
   • Black
   • Carbon
   • Blued titanium
   • M Performance style carbon

   

The Rog sound signature on the N55 six-cylinder

An inline-six sounds like no other architecture: a smooth, continuous note that becomes metallic and husky as it climbs through the revs. On the 335i, the turbo and the factory exhaust smooth out this tone to the point of reducing it to a muffled breath, far from what the N55 can produce.

On this model, two characters at the same price: the straight pipe for the raw sound of your engine, unfiltered, or the resonator for a rounder and slightly softer voice. Either way, the exhaust stays fully sporty.

With the valves closed, the Rog exhaust leaves your 335i its everyday good manners, whether sedan, coupé or convertible. With the valves open, the N55 rediscovers its straight-six song, rounder at start-up, angrier under acceleration. In the E93, with the roof folded, you enjoy it without any filter.

From order to fitting

1. Configuration

   You choose your exhaust and enter your VIN, found in box E of your registration document or at the base of the windshield.

2. Check

   We check compatibility with your VIN before manufacturing begins.

3. Manufacturing

   Your exhaust is made to order, for your car.

4. Delivery

   Free, insured to your door, tracked from dispatch.

5. Fitting

   No welding or cutting: clamps and gaskets, around two hours on a lift.

20 working days from order confirmation to delivery

Warranty

3 years, parts and workmanship, from the date of purchase

Payment

Card, PayPal or bank transfer

Installation

At the garage of your choice

What about the manufacturer's warranty on your BMW 335i N55 E90 / E91 / E92 / E93? In Europe, a manufacturer cannot refuse warranty cover simply because a part from another brand has been fitted: it has to prove that the fault comes from that part. Our article on the manufacturer's warranty.

Our recommendations for your BMW 335i N55 E90 / E91 / E92 / E93

• Daily driving

  • Stainless
  • Cat-back only
  • Rog remote

  Your BMW 335i N55 E90 / E91 / E92 / E93 stays easy to live with, the factory emissions control is retained, and you open the valves when you decide.

  View this configuration

• Fast road

  • Titanium
  • 200-cell downpipe
  • ECU remap

  More sound, more breathing, and a car you can still present at vehicle inspection.

  View this configuration

• Track

  • Titanium
  • Decat downpipe
  • Stage 2

  The most extreme configuration, for track use only.

  View this configuration

And if you are still unsure, that is perfectly normal: it is exactly why we answer every message.

BMW 335i N55 E90 / E91 / E92 / E93: your questions

Further reading

• All BMW exhaust systems
• BMW 335i N54 E90 / E91 / E92 / E93 3.0T
• BMW 325i / 330i N52 E90 / E91 / E92 / E93
• BMW M3 E90 / E92 / E93 4.0L
• Stage 2: the role of the downpipe
• How to pass vehicle inspection with a modified exhaust
• Exhaust resonator: what does it do?
• The 28 brands we cover