50 et's do it! In the previous issue of DSPORT, we introduced you to our latest D'GARAGE projects: a 2019 Subaru WRX and a 2019 Honda Civic Si. We explained that both cars will go through various stages of upgrades, and to continue measuring the progress, nosotros will race at the end of each stage on the drag strip. As you lot may have guessed, we will keep you up to engagement with our stages and race results, so be sure to keep a close eye on every issue of DSPORT besides as our YouTube channel. If you own a Subaru WRX or a Honda Civic Si, this boxing volition serve equally a map of dos and don'ts so you make the right decisions for your car and refrain from whatsoever useless upgrades. In this story, we will cover the first stage for the Subaru WRX.

Text by Bassem Girgis // Photos past Joe Singleton

DSPORT Event #208

Stage 1

We've been experimenting with numerous brand-new platforms lately, and we learned a lot about how these new ECUs bear on different platforms. While we unremarkably take a specific route for most of our Test and Tunes, we decided to switch some of the order of upgrades. By changing the order of modifications, parts that gave us no advantages in the past could show more than benefits. Stage i for this Subaru WRX volition consist of two variations of an exhaust system, followed by an ECU reflash. If yous live in California, you are almost likely aware of the stricter exhaust noise law for exhaust systems louder than 95dB at specific RPMs. Read on to see our sound testing for both the REMARK Axleback and Catback frazzle systems.

The Baseline

The 2019 Subaru WRX is equipped with a two.0-liter turbocharged, directly-injection, flat-four (Boxer) engine. The Boxer engine delivers 268 horsepower and 258 lb-ft of torque to the flywheel. On our dyno, our D'GARAGE WRX delivered 244 superlative wheel horsepower and 256 lb-ft of peak torque. Before going crazy with this baseline, read on to understand why our completely STOCK WRX delivered such high numbers to all-four of its wheels.

The Parts

We unremarkably start our Test and Tunes with an intake system, only equally of lately, we haven't been getting the results we were used to getting from this simple upgrade (we experienced lack of results while testing a Focus RS, Borough Type R, and more than). Since we live in California, we wanted to address the exhaust noise laws first, and then nosotros opted for the REMARK Axleback, given the mufflers probably serve as restrictions in the back stop of the exhaust. We and then moved on to the full REMARK catback frazzle system to see if there is whatsoever difference when we change the mid-pipe. Finally, nosotros wrapped up the offset level of upgrades with a Cobb Accessport Phase 1 91 Octane off-the-shelf map.

REMARK Axleback/Muffler Deletes

The REMARK axleback is a straight bolt-on that eliminates your factory mufflers, which are believed to be the master restrictions in the frazzle system past the downpipe (which is well-nigh likely the biggest restriction in your frazzle system). Constructed from 2.5-inch sixteen-estimate T304 stainless steel mandrel bent pipes, the axleback comes with an optional burnt stainless finish, or regular stainless end. At the finish of the high-quality, mitt-welded two.five-inch pipes are quad 3.five-inch tips. This system comes equipped with everything you demand to finish the installation, including gaskets, bolts, and basics.

REMARK Catback Exhaust

The total REMARK catback frazzle is basically the axleback plus 2 mid-pipes. You can buy them separately or as a total system. Both products come with everything you lot need for installation.

The full REMARK catback exhaust system consists of the exact same Axleback when buying it separately, with added ii-piece mid-pipes (three-inch split up to 2.five-inch). The mid-pipes use the aforementioned factory exhaust hanger locations, while providing larger diameter when compared to the mill pipes. The Catback exhaust organisation comes with the axleback above and features the aforementioned type of 16-judge T304 stainless steel pipes. This arrangement comes with everything y'all demand to successfully end the installation.

Cobb Accessport

In add-on to off-the-shelf maps and custom tuning, the Cobb Accessport tin can display merely most any gauge yous want. When mounted, y'all won't demand any additional gauges in your automobile.

If you desire quick and easy power, the Cobb Accessport will evangelize just that, and more than. This small tool unlocks hidden ability past replacing conservative factory settings in the vehicle's ECU with more than ambitious calibrations. The Accessport comes equipped with diverse off-the-shelf maps that you lot can quickly apply to reflash your ECU. Each map is ideal for a specific level of modifications. In our case, we used the Cobb Accessport Stage 1 91 Octane calibration. The Accessport offers many more features, nigh notably information-logging and live in-car performance gauges (non to mention custom tuning).

Axleback/Muffler Deletes – Dyno

After a quick installation, we strapped the WRX on the dyno to encounter if the axleback makes any difference. With the REMARK muffle deletes, the WRX delivered 248.44 peak whp and 259.63 lb-ft of meridian torque. This is a 4.63 peak whp difference and 3.16 lb-ft of peak torque. The ability and torque curves showed minimal improvement, just the real noticeable difference was the frazzle note. The REMARK axleback significantly improved and increased the exhaust note and completely changed the personality of our Subaru WRX. Does the axleback proceed the WRX legal co-ordinate to the SAE testing procedure? Well, in terms of audio, the Axleback is right on the verge of existence over 95dB, but realistically, California requires all motor vehicles to go on the mufflers, so yous just need to make this decision for yourself.

Full Catback Frazzle System – Dyno

Installing the mid-pipes is equally piece of cake equally installing the axleback. With the full system on, nosotros re-strapped the WRX on the dyno, this time delivering the same peak bike horsepower (248.67whp) and a mildly improved summit torque (261.23 lb-ft of torque). The OEM mid-pipe proved to be efficient enough from the mill, and the mufflers were causing a small-scale restriction when combined with the residuum of the stock components. However, the full catback exhaust arrangement surprised us in regards to sound, delivering a lower notation than the axleback, and an even lower notation than the factory arrangement at some RPMs. Personally, the full REMARK catback frazzle offers the all-time tone when compared to just the muffler deletes or the manufacturing plant system. Information technology's quiet when it's warm, but deep when you go on the throttle.

ECU Reflash – Dyno

In addition to the elevation ability and torque increase, the Cobb tune smoothed out the giant drop between 4,200-5,000 RPM. This completely changes the driving experience of the WRX.

It was finally time to reflash the ECU. Reflashing the WRX is as piece of cake information technology gets. You only need to follow some simple instructions on your Cobb Accessport, and y'all're all set. We chose the Cobb Stage 1 91 Octane map to start with since our WRX is near stock. On the dyno, the Cobb reflash allowed our FA20 engine to deliver a top 255.91whp and a meridian 277.82 lb-ft of torque. This is a 12.1 peak whp gain and a peak 21.35 lb-ft of torque increment. Almost importantly, the Stage 1 91 Octane tune significantly improved the massive dip in both horsepower and torque between iv,200 RPM and 5,000 RPM, which nosotros believe happens due to poor head flow design in the FA20 heads.

On the factory tune, our Subaru WRX delivered a broad range of ability numbers. Recording anywhere between 217whp and 243whp, you lot never know what you lot're getting during your pull.

While torque stayed more than consistent on the manufacturing plant tune, it notwithstanding varied between 241 lb-ft and 256 lb-ft of torque. The Cobb Accessport tune, however, delivered nearly identical numbers during every dyno pull.

Oops, Manufacturing plant Tune Sucks

After wrapping upwards this stage of our Exam and Tune, we weren't happy with the results. We've tested numerous Cobb tunes, ranging from off-the-shelf maps to complete custom tuning, and we've always experienced better results. We consulted Mike McGinnis, Senior Engine Calibrator at Cobb, and information technology turned out the manufacturing plant ECU melody is simply inconsistent. During all of our testing, nosotros like to cull the highest dyno runs recorded to ensure we are as business firm as possible. Withal, after farther analyzing all of our dyno runs, nosotros discovered how truly "all-over-the-place" the factory tune behaves. Our runs varied from 217whp to 243whp, while the Cobb melody remained almost identical the entire fourth dimension. To explain it amend, if you're driving your manufacturing plant-tuned WRX, yous could be getting 217whp during one pull, 243whp in the side by side, and anything in between in other pulls. With the Cobb melody, however, as long equally your engine is cool, you know you're getting the same amount of power each time (given yous're repeating your driving behavior). With this in mind, we tin argue that the Cobb Phase i 91 Octane Map provided a 12.1whp gain, or a 38whp proceeds, depending on the factory ECU'southward mood.

On to the Adjacent

Afterward driving the Subaru WRX with the REMARK frazzle and the Cobb Stage 1 91 Octane Tune, the fun factor has gone upward. The exhaust offers the right annotation throughout the entire RPM range and you will not go sick of it. The Cobb tune smoothens out acceleration, making it experience linear and quick, with more forgiving shifting and a much-reduced rev-hang. Next up, we volition exist bringing Mike from Cobb dorsum to experiment with some custom tuning, introduce a vertical intercooler to our FA20, downpipe, and eventually flex-fuel. Before nosotros get crazy with this WRX, however, be sure to stay up to date with our challenger, the Honda Civic Si, that volition exist wrapping up its Phase 1 of its Exam and Tune in the upcoming issue of DSPORT and on our YouTube aqueduct.