What is Turbo Lag

Turbo lag is the time it takes for a turbocharged engine to deliver its full power after you press the accelerator. It’s a result of how turbochargers work: they rely on the engine’s exhaust gases to spin a turbine, which then forces more air into the engine for extra power. The catch? It takes a moment for the exhaust gases to build up enough pressure to spin the turbine and create the boost.

In short, turbo lag is the slight delay between the request for power (your foot on the gas) and the delivery of power (the turbo kicking in).

 

 

How Turbochargers Work (in a Nutshell)

To understand turbo lag, it helps to know how a turbocharger functions:

1. Exhaust Gases as Power: The turbocharger is powered by exhaust gases leaving the engine.
2. Turbine Spins: These gases spin a turbine, which is connected to a compressor.
3. Compressed Air Boost: The compressor forces more air into the engine, allowing it to burn more fuel and generate more power.
4. The Delay: Turbo lag occurs while the turbine spools up to speed, generating the boost.

This process is why turbocharged cars feel like they have “two personalities”—a calm, laggy start that transforms into a sudden burst of speed when the turbo kicks in.

 

 

Turbo Lag in the Real World

Classic Example: The Porsche 911 Turbo (930)

Nicknamed the “Widowmaker,” the Porsche 930 Turbo from the 1970s is a legendary car infamous for its turbo lag. Drivers often described the experience as nothing, nothing, nothing—then BAM! All the power would arrive in an instant, sometimes leading to spins or crashes if the driver wasn’t prepared.

Modern Example: Mazda CX-5 Turbo

Modern turbocharged cars like the Mazda CX-5 are much better at minimizing turbo lag. While you might still notice a slight delay when accelerating from a stop or low speeds, it’s far smoother than older designs, thanks to advanced engineering.

Diesel Engines: Volkswagen Golf TDI

Turbo lag is often more noticeable in diesel engines like the Volkswagen Golf TDI. That’s because diesel engines operate at lower exhaust pressures, so it takes longer for the turbo to spool up compared to gasoline engines.

 

 

 

How Automakers Are Tackling Turbo Lag

Over the years, automakers have developed clever ways to reduce turbo lag, making modern turbocharged cars faster and more responsive:

• Twin-Scroll Turbos: By separating exhaust pulses, twin-scroll turbos (used in cars like the BMW M340i) allow the turbine to spool up more quickly.
• Electric-Assisted Turbos: Some vehicles, like the Mercedes-AMG EQ Boost models, use an electric motor to pre-spin the turbine before the exhaust gases take over. This eliminates much of the lag.
• Hybrid Powertrains: High-performance cars like the Ferrari 296 GTB pair turbocharged engines with electric motors, providing instant torque to fill in the gap before the turbo kicks in.

Conclusion

Turbo lag is a fascinating quirk of turbocharged engines that has evolved over the decades. While older cars struggled with noticeable delays, modern technology has nearly erased turbo lag in most vehicles. Whether you love the thrill of laggy turbos or prefer the instant response of today’s engineering marvels, one thing is clear: turbochargers have transformed the automotive world and continue to shape its future.