BMW i8: the three-cylinder hybrid sports car, the exhaust guide
With its butterfly doors and concept-car silhouette, the BMW i8 looks like no other car. Behind the cabin, a 1.5-litre turbocharged three-cylinder works in tandem with an electric motor. But the factory exhaust is designed to keep this combustion engine unnoticed, and the car loses part of its character as a result. With this guide, it is up to you to choose the ROG exhaust that will give your i8 a voice to match its design.
Written by ROG Motorsport · Updated
- Vehicles
- BMW i8 1.5T (2014-2019)
- Engine
- 231 to 374 hp · 320 to 570 Nm, depending on the version
- Exhaust
- Valved cat-back, built for your VIN
- Material
- 304 stainless steel or titanium
- Front section
- Optional: catted downpipe with 200 or 100 cells, or decat
- Valves
- ROG remote, or factory control if your vehicle has it
- Lead time
- 20 working days from order confirmation to delivery
- Warranty
- 3 years, parts and workmanship
The 1.5 turbo three-cylinder: the combustion heart of the BMW i8
In the i8, BMW placed a 1.5-litre turbocharged three-cylinder petrol engine behind the occupants, in a rear mid-mounted position. On its own, it produces 231 hp and 320 Nm and drives the rear wheels, while an electric motor powers the front axle. The result is a lively, effective four-wheel-drive sports car, whose combustion engine remains its most expressive part.
A three-cylinder has a naturally distinctive sound, more gravelly and more rhythmic than a four-cylinder. On the i8, the factory exhaust holds back almost all of it, and the combustion engine goes unnoticed. The ROG valved exhaust takes its place without changing anything on the engine or its electronics, and lets you make this three-cylinder heard whenever you feel like it, without giving up silence the rest of the time.
What makes up the exhaust on your BMW i8
An exhaust system is best understood in two parts. Here is what each one does, and what ROG replaces.
The cat-back is the complete exhaust system
It is everything you can see under your BMW i8, from the outlet of the front section to the tips: pipes, silencer, valves. Routing, silencer, valves: this is where the sound is shaped, and where we focus our research and development.
The front section, where the catalytic converter sits
On your BMW i8, it is the downpipe, the pipe leading from the turbo. It contains the factory catalytic converter: the second restriction in the exhaust, after the silencer. Changing this part remains a choice: it pays off mainly with an ECU remap, which turns the freed-up flow into power.
Your BMW i8 in figures
What an exhaust changes straight away is the sound, the engine's breathing and the weight at the rear. For more power, add an ECU remap.
Power
Torque
Published manufacturer and Stage 2 figures. Factory figures vary by version; Stage 2 figures published for the 374 hp version.
With or without an ECU remap, the exhaust fits and works. But it is an ECU remap at an approved tuning centre that truly unlocks your BMW i8, and that is what we recommend.
The i8's turbocharged three-cylinder does not use all of its reserve as standard, and a Stage 2 can tap into it by working on the boost. On a hybrid powertrain, this work calls for a tuner who has mastered the whole system, and the result always depends on the vehicle's condition. The ROG exhaust fits naturally into this kind of approach.
Configuring your exhaust, step by step
4 choices, in the same order as the product page configurator.
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Step 1 of 4: Material: stainless steel or titanium
For your BMW i8, the exhaust costs €2,490 in stainless steel and €2,990 in titanium.
304 stainless steel
2 490 €
- Weight
- Baseline
- Sound
- Full and rounded
Durable, corrosion-resistant, with a rounded, full sound: the most popular option.
Titanium
2 990 €
- Weight
- Around 40% lighter
- Sound
- Metallic, crystal-clear
For the same design, it weighs around 40% less than stainless steel. A more metallic note at high revs and a look all of its own, from brushed to blued.
Both materials age well: 304 stainless steel copes with winter and salt, and titanium does not rust. Stainless steel or titanium: what really changes.
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Step 2 of 4: Front section: downpipe and catalytic converter
Optional: the downpipe on your BMW i8, with its catalytic converter. Sound rating out of 10, valves open: the factory exhaust sits at 3.
Cat-back only
Included
7/10Factory emissions control
Nothing changes at the front: the cat-back alone is already enough to change the car.
200-cell sports catalytic converter
+700 €
8/10Road use and French MOT
The everyday compromise: emissions control is still there, and breathing improves noticeably.
100-cell sports catalytic converter
+700 €
9/10French MOT pass not guaranteed
One step further: more flow, a more aggressive sound, reduced emissions control.
Decat
+450 €
10/10Track use only
Everything unleashed: maximum flow and unrestrained sound, for the track.
Sound intensity, on a scale of 0 to 10
- 10/10Decat downpipe + ROG cat-back
- 9/10100-cell sports catalytic converter + ROG cat-back
- 8/10200-cell sports catalytic converter + ROG cat-back
- 7/10ROG cat-back only, factory catalytic converter retained
- 3/10Factory exhaust, for comparison
Valves open. With the valves closed, every configuration becomes discreet again.
What about the engine warning light? It can appear with a sports catalytic converter: the downstream oxygen sensor reads a different level of cleaning from the factory unit. It is not an engine fault, and it is dealt with by an ECU remap or a diagnostic tool. With a decat, an ECU remap becomes necessary. If it happens to you, call us and we will point you in the right direction. Passing the French MOT with a sports exhaust.
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Step 3 of 4: Valves: ROG remote or factory control
Two ways to control the valves on your BMW i8.
ROG remote
The simplest solution: a control unit in the boot and a remote, open or closed at the press of a button, whatever mode you are in. A question while fitting? We will get back to you.
Factory control
- Only for vehicles fitted with factory valves
- Controlled by the drive modes
Does your vehicle have factory valves? The exhaust keeps their existing control: the drive modes operate the valves, as before, with no added electronics.
On a long journey, what matters is the absence of drone at a steady speed. With the valves closed, the exhaust keeps the cabin calm; the show is still there whenever you ask for it. More about exhaust drone.
-
Step 4 of 4: Tips: the visual signature
Match the tips to the style of your BMW i8, 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 i8's three-cylinder
The i8's three-cylinder has a gravelly, rhythmic, almost rough voice that contrasts with the car's futuristic image. As standard, you only hear a distant echo of it: the factory exhaust is designed to keep the combustion engine in the background, even when it is working at full load.
In discreet mode, with the valves closed, the i8 keeps its restraint, ideal for crossing town or setting off early in the morning. With the valves open, the three-cylinder comes out of its shell: its distinctive grain can be heard with every acceleration, and the car gains a sound presence to match its looks.
From order to fitting
-
Configuration
You choose the options for your BMW i8 and enter its VIN, found in box E of the registration certificate.
-
Check
We confirm compatibility with your car before we build it.
-
Manufacturing
Made to order, for your BMW i8.
-
Delivery
Free, insured delivery, with tracking sent on dispatch.
-
Fitting
Clamps and gaskets, no welding: two hours on average at the garage of your choice.
20 working days from order confirmation to delivery
- Warranty
- 3 years, parts and workmanship, from the date of delivery
- Payment
- In instalments with Klarna
- Installation
- At the garage of your choice
What about the manufacturer's warranty? In Europe, fitting a part from another brand is not enough on its own to void it; the manufacturer has to prove the link between that part and the fault. Our article on the manufacturer's warranty.
Our recommendations for your BMW i8
-
Daily driving
2 490 €
- Stainless
- Cat-back only
- ROG remote
Your BMW i8 stays easy to live with, the factory emissions control is retained, and you open the valves whenever you decide.
View this configuration -
Fast road
3 690 €
- Titanium
- 200-cell downpipe
- ECU remap
For great roads: more voice and more response, while staying road-friendly.
View this configuration -
Track
3 440 €
- Titanium
- Decat downpipe
- Stage 2
The most extreme configuration, for track use only.
View this configuration
These profiles are starting points. The right choice is often made in five minutes on the phone.
BMW i8: your questions
How much power does an exhaust add on the BMW i8?
As standard, the BMW i8 produces 231 to 374 hp and 320 to 570 Nm, depending on the version. Without a remap, the exhaust transforms the voice and lightens the rear; it is the ECU remap that increases power.
Stainless steel or titanium: which material for the BMW i8?
For the BMW i8, the ROG exhaust costs €2,490 in stainless steel and €2,990 in titanium. Choose stainless steel for value for money and a rounded sound, titanium to save around 40% in weight and get a clearer tone.
Do you need to replace the catalytic converter on the BMW i8?
No, the cat-back alone already does most of the work on the BMW i8. The downpipe option is for those tuning the engine: 200 cells to stay road-friendly, 100 cells or decat for the track.
Can the BMW i8 pass the French MOT with a ROG exhaust?
The cat-back only and the 200-cell sports catalytic converter both keep emissions control: that is the configuration to present, with the valves closed. The 100-cell converter makes a pass uncertain, and the decat fails the emissions test on the BMW i8.
How is the ROG exhaust fitted on the BMW i8?
Fitting needs no welding or cutting and takes two hours on average on a lift. We check compatibility with the VIN of your BMW i8 before manufacturing.
What price and lead time for a ROG exhaust on the BMW i8?
From €2,490 to €3,690 depending on the configuration. Allow 20 working days from order confirmation to delivery. Free delivery in Europe, 3-year warranty.
Unsure about your configuration? Give us a call.
Stainless steel or titanium, cat-back only or the complete system: the right choice depends on how you drive and on your BMW i8. We take the time to talk it through before you order, with a reply within 24 hours. We are not here to sell to you over the phone: we help you choose, even if that means a cheaper option because it suits the way you drive.
Behind every ROG exhaust is a French team you can actually reach, who know the cars they talk about. More than 500 exhaust systems fitted and a rating of 4.9 out of 5.
Further reading
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