The newly-redesigned 2018 Subaru WRX STI keeps the same power plant (EJ25 2.5-liter) and doesn’t get any engine upgrades. Critics have said it’s the same engine the car has had with no power upgrades since 2008 when they bumped the EJ25 up from 300hp to 305hp in the third-generation STI. Performance fans want to know why and Subaru has answered.
On their Global WRX STI page, Subaru has answered critics and says its about the overall feel and not just power. They say its more about synergy (the sum of the parts) than it is about power. Their website says, “While the EJ25 2.5-liter turbocharged Subaru boxer engine generating 221 kW (305hp) and 407 Nm of torque (290 lb. ft of torque) provides electrifying acceleration, driving performance isn't just about numbers. That's why the WRX STI was revamped to enhance overall driving feel.”
WRX STI gets significant upgrades
The 2018 performance sedan gets revised suspension tuning, a revised DCCD AWD system, significantly upgraded Brembo brakes, improved 6-speed manual gearbox, and new 19-inch alloy wheels. The sum of the parts equals improved handling, driving dynamics and cornering performance, and “optimum differential control even on snowy roads” over the 2017 model.
While the 2018 STI didn’t get any power increase, there’s improved performance when you look at the sum of all the parts. Synergy is a wonderful thing, and Subaru knows how to add it all up to make the whole better. Subaru answers critics saying, “Combined with the stopping power from its Brembo brakes and cross-drilled rotors, the WRX STI is more communicative, more responsive, and more exciting to drive in many situations.”
Subaru upgrades the limited edition Type RA EJ25
We are seeing Subaru make some changes to the EJ25 in the new limited edition 2018 Subaru WRX STI Type RA. Subaru announced it gets an “estimated” 310hp an additional 5 horsepower upgrade over the standard 2.5-liter EJ25 turbo boxer engine. The torque stays the same at 290 lb. ft of toque.
Subaru Tecnica International (STI) worked in some new engine mods using an STI-specified new cold air intake and high flow performance exhaust. A retuned ECU and stronger pistons also contribute to the increased engine performance.
In the Japan-only limited edition 2018 Subaru WRX STI S208, the Japanese automaker runs a hand-built EJ20 2.0-liter turbo boxer with more power than the EJ25. STI increased the maximum power output in the engine to 330PS (325hp).
Subaru has not confirmed this, but we are speculating they will increase power in the EJ25 or change to the WRX-sourced FA20 2.0-liter DIT engine and increase power when they bring out the fifth-generation STI in 2020. That’s when its due for a complete remodel and will get the new Subaru Global Platform. Big changes are coming for the WRX STI, but fans will have to wait. Until then, the current generation performance sedan does get significant improvements to enhance the overall driving dynamics.
Photo credit: Subaru