Turbos Explained: How Turbochargers Actually Work (Without the Engineering Degree)

Matthew Forde
May 12
3 min read

Let’s be honest—if you’ve ever nodded along during a car meet while someone ranted about “spool time” and “PSI,” but had no idea what was happening… you’re not alone.

This is your no-fluff, beginner-friendly guide to turbochargers.We’ll break down:

What a turbo actually is
How it works
Why it makes your car faster
The pros, cons, and myths
And what boost really means

Let’s turn that “I kinda get it” into “I actually know what I’m talking about.”

🌀 What Is a Turbocharger?

A turbocharger is a forced induction system that increases the power of your engine by cramming more air into it.More air = more fuel = more boom = more horsepower. Simple math.

It’s like giving your engine a Red Bull—but mechanical.

🔧 How Does a Turbo Work?

Here’s the breakdown in plain English:

Exhaust leaves your engine
That hot exhaust gas spins a turbine wheel
The turbine is connected by a shaft to a compressor wheel
The compressor sucks in fresh air and forces it into the engine
Your engine gets a denser air/fuel mix, and makes more power

You're literally reusing exhaust to make power. Efficiency king.

📏 What’s “Boost” Then?

Boost is the pressure created by the turbo when it forces more air into the engine. It’s measured in PSI (pounds per square inch) or bar (if you’re European or bougie).

A naturally aspirated (non-turbo) engine runs at atmospheric pressure—about 14.7 PSI.
A turbocharged engine can hit 10–30 PSI of boost, depending on tuning, build, and if the owner hates reliability.

🐢 What’s Turbo Lag?

Turbo lag is that slight delay between hitting the gas and the boost kicking in. It happens because your turbo needs exhaust pressure to spool up. No spool = no boost = “Why isn’t my car moving?”

Newer cars use:

Twin-scroll turbos
Ball bearings
Electric assist (hi Porsche)…to reduce lag and bring in boost quicker.

🆚 Turbo vs Supercharger (Quick Comparison):

Feature	Turbocharger	Supercharger
Power Source	Exhaust gas	Engine belt
Boost Timing	Lag, then power	Instant response
Efficiency	More efficient	Less efficient
Sound	Pssshhh (blow-off)	Whiiiiine

TL;DR:

Want that sudden kick? Go turbo.
Want linear, no-lag power? Go supercharger.
Want both? Twincharged cars exist, but so does bankruptcy.

🔥 Pros of Turbocharging:

✅ More power from a smaller engine
✅ Better fuel economy when off boost
✅ Endless tuning potential
✅ That sweet, sweet spool and blow-off valve sounds

⚠️ Cons of Turbocharging:

❌ Turbo lag (especially on big turbos)
❌ More heat = more strain on engine
❌ Maintenance and tuning knowledge required
❌ Not all “turbo’d” cars are built right (shoutout to Craigslist builds)

🧪 Types of Turbochargers:

Single Turbo: Most common. Good for simplicity and reliability.
Twin Turbo: Two smaller turbos. Less lag, more power.
Twin-Scroll Turbo: A smarter single turbo with two exhaust channels.
Variable Geometry Turbo (VGT): Adjusts turbine shape. Found in high-end cars and diesels.
Electric Turbo: Uses electricity to spool faster (usually combined with hybrids or performance EVs).

🏁 What Cars Come With Turbos From the Factory?

Volkswagen GTI
MazdaSpeed3
Subaru WRX
Ford EcoBoost lineup (Mustang, F-150, Focus ST)
Volvo T5/T6 models
BMW 335i, M340i, etc.
A90 Supra (Toyota, but it's a BMW—let’s not argue)

There are tons of beginner turbo cars out there with real tuning potential.

🛠️ Want to Turbo Your Car?

You’ll need more than just a turbo kit. Be ready to upgrade:

Intercooler
Fuel system
Exhaust
Engine internals (if going high boost)
ECU tuning
And cooling. Always cooling.

Turbocharging a car is not a bolt-on-and-go mod. It’s a full system commitment—like a performance marriage, but with more blow-off.

💡 Common Turbo Myths (Busted):

❌ “Bigger turbo = better.”Nope. Bigger turbo = more lag. You want balance.

❌ “Turbo cars are unreliable.”Not if they’re built and tuned right. Blame the owner, not the turbo.

❌ “All turbo cars are fast.”Some factory turbo cars just make up for low displacement. They're not all rockets.

📘 Ready to Actually Understand How Cars Work?

Grab Learning About Cars for Beginners and The Car Bible.Both are written in a way that’s sarcastic, simple, and brutally honest—so you never have to fake your way through a car convo again.

💬 Comment Prompt:

Have you ever driven a turbo car that surprised you—or disappointed you? Drop the name and the reason. I’ll wait.