Top 5 Most Efficient Engine Power Mods for WRX/ STi/ LGT/ FXT/ OBXT:

  • Johann Ave
  • 22 April, 2019

 

 

1.)  Tuning

   Before modifying any stock vehicle, it is imperative that you are able to tune the engine’s parameters to get the most from any mod you do.  Fuel, Ignition Timing, Boost are just a few of the parameters that can be modified to help increase performance safely.  There are many tuning methods and products on the market, but the most widely accepted and supported for the Subaru platform is the COBB Accessport.  This device plugs in via your stock OBD2 port and then can overwrite and change the ECUs parameters.  It’s a must have for anyone looking to increase the performance of their car.  The Accessport and many other tuners are also capable of data logging, as well as real time monitoring of critical variables when running a high-performance vehicle.  It also can read and erase engine codes to help diagnose and sort through issues that might occur.  As you make mechanical changes to your car to increase output you are also improving the engine’s ability to breath better and run cooler, but those changes can cause other issues that the ECU is not calibrated to handle and that is where the Tuners come into play.

For pricing and applications, click here.


2.)  Intake

   In order for the car to be able to increase its output, you first need to help aid its input.  The easier the engine can breathe, the faster it will be able to increase its boost and power.  An easy way to improve this is by replacing, or modifying your engine’s air intake.

This can be done in a few different ways.  You can replace the panel filter in your stock air box to a higher flowing unit.  This is good for increasing performance and MPG, but also retains an OE look and keeps all the OE silencers intact for those looking to keep intake noise to a minimum. Short Ram and Cold Air intakes are the most commonly used methods.  A Short Ram intake uses a high flow cone style filter and high flowing piping to pull more air into the engine from inside the engine bay.  Some Short Ram Intake systems include a custom heat barrier to prevent hot air from reaching the air filter, though it is not as efficient as a Cold Air intake. A Cold Air Intake uses the same components as a Short Ram system but relocates the filter inside of the bumper, away from the heat of the engine to help further increase efficiency and boost output. Once installed the engine can be re-calibrated with a tuner to increase its boost, fuel, and timing to further increase its efficiency and drive-ability.

 For pricing and applications, click here.


3.) Exhaust: Turbo-Back and Up-pipes

   One of the most restrictive parts of your Subaru’s engine is its exhaust system.  Due to regulations of emissions and decibel levels in some areas, the Stock Exhaust system has been restricted to make your Subaru compatible within all jurisdictions. Exhaust components such as Up-Pipes, Down-pipes, and Cat-Backs are all designed to increase the flow of the exhaust leaving the engine to help it breath more efficiently and spool up the turbo faster.

   Many Subaru’s have a catted up-pipe as part of their factory exhaust system. This factory part can create issues with both performance and reliability of your vehicle. Subaru’s pre-turbo up-pipe catalytic converters are known to clog and potentially break apart sending debris into the turbo’s exhaust turbine. In most cases when this happens the turbo is damaged which can result in $$$ repairs. Upgrading your factory up-pipe can increase turbo spool and prevent premature mechanical failure.

   A new Turbo-Back Exhaust System is a great way to increase the efficiency of your engine.  Most turbo-back systems are comprised of the Down-pipe (or J-pipe), cat-back (or mid-pipe), and axle back components. The combination of these parts will reduce exhaust back pressure and further increase the engine’s breathability.  This in conjunction with tuning, will also allow the car to run more boost into the engine which combined with more fuel will increase performance.

For pricing and applications, click here.

 


 

4.)  Air/ Oil Separator

   This part does not increase performance, but is a must for any performance build.  The Subaru boxer engine has a pretty extensive oil breather system and that system can leave a lot of oil residue in the intake system, turbo, intercooler, and manifold.  An AOS or Air/ Oil Separator is much like an Oil catch can but has a few added features that make is superior.

   The purpose of an AOS is to take the oil vapor (oily air) that comes from the engine’s block and then condenses it in a baffled tank to separate the oil from the air.  The AOS then drains the condensed oil back into the block where it belongs, and allows cleaner air vapor to enter the intake system.  This will not only help with keeping the inside of your intake components clean, but will also help with crank case pressure and oil consumption.

   There are many Air/ Oil Separators on the market, but we prefer the Crawford above all else.  The Crawford unit has a heated base that helps keep the condensed oil viscous and able to drain back into the block without building up in the tank or clogging the drain hose.  It also has a unique routing system if its hoses that delete the PCV which is a valve in the OE breather system that can cause some serious oil consumption issues if it fails.  Increasing performance is a fun endeavor, but you also need to make sure that you cover your bases and help the engine maintain that performance is just as important.

For pricing and applications, click here.


5.)  Turbochargers/ Fuel Injectors 

   One of the biggest increases in power you can make on a turbocharged car is to increase the amount of air and fuel going into the engine.  You can turn up the boost on the stock turbocharger to a certain point to make more power but they are limited to a lower output range for reliability.  To push your output numbers up you need a larger turbo and in turn larger fuel injectors.  You will need to have a custom tune created by a reputable tuner when these components are upgraded, but the results can be profound.  There are many different sizes and types of Turbochargers as well as injectors that can be selected to best suite the power output or driving characteristics of your car.  Please feel to contact us with any questions and we will be happy to present you with our recommendations to best suite your needs.

For pricing and applications for Turbo Chargers, click here.

For pricing and applications for Fuel Injectors, click here.

 

* If you are looking to order parts that cannot be found in our catalog, let us know! We are constantly adding new products to our website. You can email part inquiries to: info@nwrallysports.com


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