Whether you’re working with a base WRX platform, or you have a decked-out STI with performance seats to match, both of these rally-inspired, all-wheel-drive sedans are similar on the surface and share a chassis, but upon further inspection, the different equipment and performance components result in significant performance and aesthetic variations between the two. Before deciding on the right performance parts for your WRX or STI, let's compare a few of the major differences and how they impact performance and rideability. 

WRX Versus STI Performance Characteristics 

The WRX’s 2.0-liter direct-injection, four-cylinder engine is rated at 268 horsepower and 258 pound-feet of torque. The STI’s 2.5-liter direct-injection, four-cylinder engine is rated at 310 horsepower with 290 pound-feet of torque. The WRX comes with a standard 6-speed manual transmission, with available Lineartronic for automatic shifting. The STI is only available with a close-ratio 6-speed manual transmission with all-wheel drive. Other notable performance characteristics between the two include: 

  • Braking: The WRX comes with a standard Subaru braking system; the STI is equipped with bigger Brembo brakes. You can upgrade WRX brakes to match the more responsive stopping power of an STI with ease. 
  • Suspension: Both the WRX and STI share a double-wishbone lateral link with pillow-ball bushings in the rear. On the front end, the WRX has an aluminum strut-type system with pillow-ball joints, while the STI is equipped with an aluminum inverted strut with pillow-ball joints. If you’re looking for a tighter suspension on either model, check out these versatile suspension upgrades for improved handling and notable performance prowess.
  • Spoilers: The WRX is equipped with a subtle lip spoiler, while the STI’s winged spoiler is designed to improve traction and downward force. Available with or without the wing, the STI’s wing can add up to 3MPH to top speeds. You can easily add a new spoiler to either model.

  • Performance Modes: Both the WRX (on CVT models) and the STI feature Subaru intelligent-drive systems. The 3 modes include intelligent, sport, and sport sharp for noticeable variations in steering, responsiveness, and braking. 

  • Other Key Factors of STI Versus WRX

  • Fuel Economy: The main difference between the WRX and the STI’s fuel economy is how they are intended to be used. If you are looking for a sports car that is better for daily driving, the WRX gets better gas mileage averaging at 23 MPG versus the STI that averages 18 MPG.
  • Power: The WRX spools faster versus the STI, which is more friendly for daily driving. STI on the other end is more track-oriented and requires higher rpm to stay in boost. Both the WRX and the STI can go from 0-60 MPH at the same rate. If you are looking to build high power STI will be the way to go.
  • DCCD: The Driver Control Center Differential allows the STI center differential locking to be dialed in and adjust the handling. Allowing the driver to adjust the torque of the front and back wheels. This gives the STI an edge over the WRX when it comes to controlling speed and power.
  • Aesthetic Upgrades Reduce Drag on the WRX & STI

    Since both the WRX and STI share similar shaping, there are many versatile body kits and options like the 2015-2017 WRX carbon fiber front lips for a boost in style and aerodynamics. With streamlined skirting for reduced drag, an updated spoiler for improved road traction, or if you’re simply after a customized look that reflects your style, many of our latest upgrades combine the best of function with professional appeal. 

    For every gear head out there, these remarkable sports sedans were practically built to be upgraded for maximized performance on the track. From elegant 2015+ STI side skirts to new shifters, steering wheel grips, and more, explore our expertly engineered upgrades and you’ll find that there are virtually limitless routes you can take to make the WRX or STI your own.