What is the 3S Engine?

The 3S engine, also known as the Toyota 3S-GTE engine, is a twin-turbocharged, inline-four, 2.0-liter engine produced by Toyota from 1986 to 2007. It was used in various Toyota models, including the Celica GT-Four and the MR2 Turbo, and is renowned for its durability, performance, and strong following among car enthusiasts.

Engine Specifications

The 3S-GTE engine has a cast-iron block and an aluminum cylinder head. It has a bore of 86 mm and a stroke of 86 mm, resulting in a displacement of 1,998 cc. The engine has a compression ratio of 8.5:1, which is relatively low for a turbocharged engine, but helps to prevent engine knocking and improve reliability.

Turbocharger System

what is 3s engine

The 3S-GTE engine uses a parallel twin-turbocharger system, with each turbocharger serving two cylinders. This design provides a more efficient and responsive power delivery compared to a single-turbocharger setup. The engine has a maximum power output of 252 horsepower at 6,000 rpm and a maximum torque output of 217 lb-ft at 3,200 rpm.

Advanced Features

The 3S-GTE engine is equipped with several advanced features that contribute to its performance and efficiency:

  1. Water-Cooled Intercooler: The engine has a water-cooled intercooler to reduce intake air temperature and increase engine power.
  2. Variable Valve Timing (VVT-i): The engine uses a variable valve timing system (VVT-i) to optimize engine performance and fuel efficiency.
  3. Knock Sensor: The engine is equipped with a knock sensor to detect and prevent engine knocking, which can cause damage if left unchecked.
  4. Dual-Mass Flywheel: The engine has a dual-mass flywheel to reduce engine vibration and improve drivability.

Maintenance and Tuning

While the 3S-GTE engine is known for its durability, it can be challenging to work on due to its complex design and the need for specialized tools and knowledge. Here are some DIY tips for maintaining and tuning the engine:

  1. Use High-Quality Parts and Fluids: Ensure optimal performance and longevity by using high-quality parts and fluids, such as engine oil, fuel, and filters.
  2. Follow Maintenance Schedule: Adhere to the manufacturer’s recommended maintenance schedule and use the correct torque specifications for all fasteners.
  3. Use High-Octane Fuel: Use a high-quality fuel with an octane rating of at least 91 to prevent engine knocking.
  4. Install a Boost Controller: Use a boost controller to regulate turbocharger boost pressure and prevent engine damage.
  5. Monitor Air/Fuel Ratio: Use a wideband air/fuel ratio gauge to monitor engine performance and adjust fueling as needed.
  6. Utilize Diagnostic Tools: Use a scan tool to monitor engine parameters and diagnose any issues.
  7. Maintain Proper Lubrication: Use a high-quality oil filter and oil to ensure proper lubrication and protection.


The Toyota 3S-GTE engine is a remarkable example of engineering excellence, combining advanced features, impressive performance, and remarkable durability. While it may be challenging to work on, the engine’s strong following among car enthusiasts and its proven track record make it a highly sought-after powerplant for those seeking a reliable and powerful turbocharged engine.


  1. Control of Air Pollution From Motor Vehicles – Federal Register
  2. FAA Order 8110.4C Chg 7 – Type Certification
  3. FAA Order 8110.4C Type Certification with changes 1-5