Choosing the Best Turbo Kit for Your S55
The BMW S55 engine in the F80 M3 and F82 M4 is one of the most capable platforms for making serious power.
But once you move past basic bolt-ons, your turbo setup becomes the most important factor in your build.
The problem?
There are multiple options—and not all of them are built for the same goals.
This guide ranks the top 3 turbo kits for the S55 based on:
- Power potential
- Reliability
- Driving experience
- Overall value
🥇 #1 – 4N Motorsport Single Turbo Kit (Best for Maximum Power)
If your goal is to build a high horsepower S55, this is the top choice.
Why It Ranks #1
- Built for extreme performance
- Proven in high-horsepower builds
- Designed for maximum airflow and boost
Performance
- 700–900+ WHP potential
- Strong mid-range and top-end power
- Aggressive power delivery
Pros
- Highest power ceiling
- Race-inspired design
- Excellent for big turbo builds
Cons
- Higher cost
- Slightly later spool
- Requires full supporting mods
👉 Best For:
Serious enthusiasts chasing maximum power and performance builds
🥈 #2 – Big Boost Single Turbo Kit (Best All-Around Setup)
Big Boost offers one of the most balanced turbo solutions for the S55 platform.
Why It Ranks #2
- Flexible turbo sizing options
- Strong balance of power and drivability
- Great for street and performance builds
Performance
- 650–850+ WHP potential
- Faster spool (depending on setup)
- Smooth, linear power delivery
Pros
- More customizable
- Better street drivability
- Strong performance gains
Cons
- Slightly lower peak power than 4N
- Still requires full supporting mods
👉 Best For:
Drivers who want a fast, usable street car with serious power
🥉 #3 – Pure Turbos (Upgraded Twin Turbo Setup)
Not everyone wants to go single turbo—and that’s where upgraded twins come in.
Why It Ranks #3
- Retains factory twin turbo layout
- Faster spool than single turbo setups
- Easier transition from stock
Performance
- 550–700+ WHP potential
- Strong low-end response
- Smooth power curve
Pros
- Quick spool and response
- More OEM-like driving feel
- Less drastic change from stock
Cons
- Lower power ceiling
- Still limited compared to single turbo setups
👉 Best For:
Enthusiasts who want quick response and strong performance without going full single turbo
Single Turbo vs Twin Turbo (Quick Insight)
Single Turbo
- Higher horsepower potential
- Strong top-end performance
- More aggressive driving feel
Twin Turbo (Upgraded)
- Faster spool
- Better low-end response
- More daily-driver friendly
What You Need to Support Any Turbo Upgrade
No matter which kit you choose, these are required:
- Fueling upgrades (port injection recommended)
- Intercooler upgrade
- Intake system
- Performance exhaust
- Custom tuning
Skipping these is one of the biggest mistakes builders make.
Which Turbo Kit Is Right for You?
Choose 4N Motorsport if:
You want the most power possible
Choose Big Boost if:
You want balance between power and drivability
Choose Pure Turbos if:
You want fast spool and OEM-like feel
Final Thoughts
There’s no one-size-fits-all answer when it comes to turbo kits for the S55.
It all comes down to your goals:
- Maximum power → 4N Motorsport
- Balanced performance → Big Boost
- Quick response → Pure Turbos
The S55 platform is capable of incredible performance—
the right turbo setup is what unlocks it.
FAQ
Q: What is the best turbo upgrade for BMW S55?
A: The 4N Motorsport single turbo kit is best for maximum power, while Big Boost offers a more balanced setup.
Q: How much horsepower can an S55 handle?
A: With proper mods, the S55 can support 700–900+ WHP.
Q: Is single turbo better than upgraded twins?
A: For high horsepower builds, yes—but upgraded twins offer better spool and drivability.