Subaru’s 2020 WRX is now fully supported within the COBB product line.  We have confirmed fitment of our bolt-on upgrades such as the Big SF Intake System, 3″ Turboback Exhaust (both Resonated and Non-Resonated), and Air/Oil Separator.  The SUB-004 Accessport comes loaded with Off The Shelf Maps to support all of our common bolt-on upgrades.  For those interested in taking their 2020 WRX beyond the scope of our Stage Power Packages and Off The Shelf Maps, Subaru Accesstuner and Accesstuner Pro both now offer full tuning support, including COBB Custom Features.

For a complete list of compatible parts, visit the 2020 Subaru WRX MT USDM Vehicle Page on the COBB Tuning website!  Have a different model year? See our expansive list of WRX aftermarket parts.

Subaru Accessport V3 (AP3-SUB-004)

The Accessport is the world’s best selling, most flexible, and easiest to use ECU upgrade solution for your Subaru. Unlock power hidden within the vehicle by replacing conservative factory settings with more aggressive calibrations. Follow our staged upgrade path with pre-loaded Off The Shelf (OTS) maps or use custom mapping for any modification level. It’s the last engine management solution you’ll ever need. Subaru Accessport V3 (AP3-SUB-004)

Off The Shelf Maps

Off The Shelf Maps for the 2020 WRX 6MT are the first to use our CCFv2 ECU type, taking advantage of features such as MAF Simple and Closed-Loop fueling to deliver higher, more consistent power.

Each Accessport comes pre-loaded with an assortment of Off The Shelf Maps that support from a completely stock car up to a car with a full turboback exhaust and COBB Big SF Intake System.  Map files are available for cars using either 91 or 93 octane fuel.  Stage 1 and Stage 1+BigSF map produces peak gains of +14% HP / +13% TQ over stock and maximum gains of +98% HP / +98%TQ over stock when using 93 octane fuel. Stage 2 and Stage2+BigSF produce peak gains of +19%HP / +40% TQ over stock and maximum gains of +110% HP / +110% TQ over stock when using 93 octane fuel.  Due to the significant power drop observed at redline on the stock calibration, percent gains are drastically different than previously published.  With OTS Maps carrying power out all of the way to redline, the differential at 6800 RPM is over 100% for both horsepower and torque.  As you can see in the graphs below, this is obviously an extreme condition.  We are still seeing significant gains across the entire RPM range and.  Cars utilizing a Stage1+BigSF or Stage2+BigSF map with the COBB Big SF Intake System can expect to see 10-12 HP in addition to the presented non-SF dyno charts.

*For a complete explanation of each Off The Shelf Map for the 2020 WRX, visit our Map Notes Page.

The following map files are available for the 2020 WRX 6MT via a firmware update through Accessport Manager or via download on the COBB website.

• Stage0 v350.ptm
• Stage1 91 v351 HWG.ptm
• Stage1 91 v351 LWG.ptm
• Stage1 91 v351.ptm
• Stage1 93 v351 HWG.ptm
• Stage1 93 v351 LWG.ptm
• Stage1 93 v351.ptm
• Stage1 Economy Mode v351.ptm
• Stage1 Valet Mode v351.ptm
• Stage1+BigSF 91 v351 HWG.ptm
• Stage1+BigSF 91 v351 LWG.ptm
• Stage1+BigSF 91 v351.ptm
• Stage1+BigSF 93 v351 HWG.ptm
• Stage1+BigSF 93 v351 LWG.ptm
• Stage1+BigSF 93 v351.ptm
• Stage1+BigSF Economy Mode v351.ptm
• Stage1+BigSF Valet Mode v351.ptm
• Stage2 91 v350 HWG.ptm
• Stage2 91 v350.ptm
• Stage2 93 v350 HWG.ptm
• Stage2 93 v350.ptm
• Stage2 Economy Mode v350.ptm
• Stage2 Valet Mode v350.ptm
• Stage2+BigSF 91 v350 HWG.ptm
• Stage2+BigSF 91 v350.ptm
• Stage2+BigSF 93 v350 HWG.ptm
• Stage2+BigSF 93 v350.ptm
• Stage2+BigSF Economy Mode v350.ptm
• Stage2+BigSF Valet Mode v350.ptm
• Vehicle Anti-Theft Mode v350.ptm

2020 Subaru WRX Stage Power Packages

COBB Stage Power Packages take the guesswork out of upgrading your 2020 WRX.  We have combined our precision engineered bolt-on parts with the Accessport and professionally calibrated Off The Shelf Maps to create a completely turn-key package.  Keep it mild with a Stage 1+Big SF Package or maximize airflow with the COBB Stage 2+Big SF Package!

Accessport V3 Big SF Intake System	Accessport V3 Stainless Steel 3″ J-Pipe Stainless Steel 3″ Cat-Back Exhaust	Accessport V3 Big SF Intake System Stainless Steel 3″ J-Pipe Stainless Steel 3″ Cat-Back Exhaust

*Visit the 2020 WRX MT USDM Vehicle Page for a complete list of compatible products.

Miscellaneous Accessport Firmware Updates

In addition to new vehicle support, Subaru Accessport firmware also received some miscellaneous updates to improve Protuner workflow and streamline customer experience.

Remote Accessport Part Number Changes

Accessport firmware for all USDM Subaru Accessports (AP3-AU-SUB-003 and AP3-AU-SUB-004 excluded) are now eligible for remote part number changes.  Previously, Accessports needed to be shipped to COBB in order to have their part numbers changed

Reflash-Only Map File Support

Accesstuner and Accesstuner Pro both now have the ability to save a map file as a “Refresh Only” file.  This feature prevents Accessport users from making a Realtime map change when a Reflash-Only map file is flashed to the ECU.  This toggle has been activated for the 2019-2020 Subaru Ascent OTS Map files and will be utilized in additional OTS files moving forward.

Addressed N/A Datalog Bug

In previous firmware versions, an Accessport would create a corrupt and unusable datalog file even when too many monitors were selected and data logging was not possible.  This bug has been addressed to prevent the Accessport from creating unusable files in this situation.

Subaru Accesstuner Updates

Subaru Accesstuner is receiving significant updates as a part of this release.  Not only will it now be compatible with both the 2020 WRX and 2020 STI, our Gen2 Custom Feature set is now available to end users.  All of the features listed below can now be found within a new ECU type dubbed “COBB v4.0 CCF (Custom Features Gen2)”.  A large change from our previous CCF release for DIT WRXs is the inclusion of support for cars equipped with a CVT transmission.  This ECU type is also based on Subaru’s latest factory programming which includes improvements for longer battery life, and more.

• Speed Density Tuning
  • The COBB Speed Density feature is a powerful yet easy-to-use solution that integrates Speed Density tuning into the Subaru engine control unit (ECU) and can be used to entirely replace or work in conjunction with the existing factory mass airflow (MAF) sensor. It is highly customizable and features such as real-time tuning aid in a speedy and efficient tuning process.  This tuning strategy is especially useful on vehicles that exceed the capabilities of the factory MAF sensor, or on vehicles where mechanical configuration causes inaccurate or noisy MAF readings.
• Boost Gauge Wrap
  • This feature has been available on VA STIs and allows for the factory boost gauge to “wrap” to display boost values beyond the factory 24psi limit.  When wrapped, the gauge will display up to 44psi. The base value can be customized for easier on-the-fly monitoring.  You will need an aftermarket MAP sensor with the appropriate higher range in order to utilize this feature.
• Boost Extend
  • In order to properly facilitate boost beyond the factory 24psi hard limit, several new tables and monitors have been created. These changes allow for higher limits for boost targeting, boost limits fuel cut, and boost monitoring. You will also need an aftermarket MAP sensor with the appropriate higher range in order to read beyond the factory limits.
• Boost Smoothing
  • This allows for custom changes to separately filter out “noise” in the pressure reading used in boost control and SD without impacting other ECU functions that use manifold pressure.
• IPW Extend
  • In order to facilitate IPW beyond a stock hard coded limit pre-fuel pressure compensation, custom code has enabled a new limit more than 10x the stock one, making it unlikely to ever be exceeded
• Knock Sum Monitor
  • This new monitor increments when the ECU’s knock signal algorithm perceives a knock event.  This is the same signal used by the the knock response systems (Feedback Knock, Fine Knock Learning, and DAM).  The overall count is not entirely relevant, instead the conditions of the log when the sum increments are more important.
• Load Extend
  • The extended load tables have a new limit of 10.2 g/rev which should facilitate engines making ~1000 ft lbs of torque or less without requiring any skewing of load.
• MAF Simple
  • The MAF Simple feature allows you to transition from the highly complex factory airflow model to a simple MAF calibration based airflow calculation at higher load/boost.  This makes tuning cars that are close to exceeding boost/load limits.

For details specific to these features, see our help documents below:

• Subaru DIT V4.0 CCF (Gen2) Additions
• Subaru Speed Density Guide: 2.0, 2.5L, DIT

For now, these features are only available in Accesstuner Pro HL, so contact your preferred Authorize Protuner to have them added to your custom tune.  In the future, we will move these features to the end-consumer version of Subaru Accesstuner.