2015 Subaru WRX and STi Modifications to Increase Horsepower


The Best 2015 Subaru WRX and STi Modifications

For the 2015 model year, Subaru has done what many never expected – split up the WRX and STi versions of its popular Impreza all-wheel drive Rally inspired four door. That’s right, the WRX and STi no longer share the same engine. While still featuring many of the same differences as prior generation, this is a big step for Subaru as they explore many new avenues and technologies with the 2015 WRX.

2015 STi vs 2015 WRX

Let’s start with the 2015 STi, as not much has changed with this model. It still retains many of the same old technology seen in prior generations. It makes sense for Subaru to hold back on any drastic changes where it matters the most, as the STi is one of the leading sellers in their current lineup. The engine remains an EJ257 using the same journal bearing turbocharger seen in past models, making an acceptable 305hp. Subaru did get into changing up the suspension a bit, making it stiffer and more refined for the road, but the AWD system remains the same as the last generation. In the end, the only big change for the 2015 STi is the exterior, taking up just a few more inches in parking spaces and giving it back to the interior occupants.

On the other hand, the 2015 WRX got major changes that affect every aspect from performance to handling. It also got a nice exterior makeover that many say makes it look better than the STi. New for the 2015 WRX is the engine, a shiny new FA20DET seen in the Forester XT and teasing it’s Subaru cousin’s N/A FA20. A twin scroll turbocharger helps propel it to an impressive 268hp, while direct injection helps rocket it to 16psi boost (from the factory!). The AWD system isn’t too terribly exciting as far as new-ness, but a 6-speed transmission helps push it down the road, while the refined suspension keeps it comfortable. The 2015 WRX cashes in at a few thousand cheaper than the 2015 STi, leaving it the more affordable option for AWD-turbo junkies!

Best 2015 Subaru STI Mods

2015 STi Intake: There are many brands that deliver great products at affordable, budget friendly prices. A quick search finds options from Mishimoto, Perrin, COBB Tuning, and AEM. From that list, AEM is one of the most recognizable names offering the most complete intake kit including air filter, heat shield, and intake pipe at the lowest cost. I imagine most companies will jump on board and start producing aftermarket 2015 STi intake systems, so keep an eye out for future offerings.

2015 STi Exhaust: For the exhaust, you really can’t go wrong with any choice you make. The 2015 STi exhaust is pretty restrictive from the factory, so utilizing a full turbo-back exhaust is recommended. If you’re on a budget, however, a plain jane 2015 STi catback will give adequate improvements in exhaust flow to increase power and torque. Many name brand exhaust systems are available for purchase from many online vendors, but ETS has become a reliable company producing quality parts for budget minded and cost indifferent owners alike.

2015 STi Tuning: Tuning has become much easier over the last 10 years. It has quickly become the fastest growing technology on the aftermarket today, earning the most power and torque in the process. There are only a few 2015 STi Tuning modules now on the market, making this decision easier than any other. COBB Tuning 2015 STi tuning module is one of the easiest modules to use- EVER! Its easy to read display and easy to understand layout make it the best option for not only the 2015 STi, but also many other cars on the market!

Best 2015 Impreza WRX Mods

2015 WRX Intake: Similar to the STi, chosing the best 2015 WRX intake system is a difficult decision. Many of the same kits are available for both platforms, with full kits from Perrin Performance, ETS, Injen, and AEM. COBB Tuning offers a complete kit including silicone intake pipe, air filter, and support bracket for the lowest price point compared to similar kits, while full kits from AEM and Injen are also available.

2015 WRX Exhaust: The best exhaust system for a 2015 WRX depends on what you want to do with the car. Catbacks are the best choice for daily driver vehicles, but full turboback systems are the definitive choice for racers and rally driven cars. Basic axle back exhausts do exist, but offer littler performance benefits and are more designed for changes in exhaust tone. Invidia has the largest selection of 2015 WRX exhausts, offering turboback, catback, and axleback exhausts at an affordable, budget friendly price while meeting high quality material requirements.

2015 WRX Tuning: Much like the 2015 STi, the only plug and play tuning device for the WRX comes from COBB Tuning. The same can be said about this unit as the STI, as it’s the same module just with different ECU tunes. Go with COBB Tuning, you won’t regret it.

Final Conclusion

Buy the aftermarket parts you can afford, but beware of bad materials used in the manufacturing process which can lower the life of the parts. Consider your power goals and the intended use of the car, and chose the best 2015 Subaru parts according to your budget and plans for the car. You’ll thank yourself in the end!


Source by Alex Kollos

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