Subaru Updates : Accessport Fast Flashing and COBB 20g Turbo!!

2015 Subaru STI

The Subaru group has been quite busy as of recent, we’re excited to announce the release of some awesome Accessport updates as well as our new COBB 20g turbocharger for the 2008-2015 STI.

Accessport Updates (AP3-SUB-004:

SUB-004 Accessports received an update that significantly improves flash times on Subaru DIT ECUs.  These improvements reduce Install and Uninstall times by over 60 seconds, now coming in right at 2 minutes.  Protuners, rejoice!  Change map times have been improved by 93%, now taking less than 20 seconds!

With R&D completed on 2015 WRX 6MT cars with a full turbo-back exhaust, we’ve renamed the “Stage1+TBE” maps to a more conventional “Stage2″ naming strategy.

  • Stage2 91 v115.ptm
  • Stage2 93 v115.ptm
  • Stage2 Economy Mode v115.ptm
  • Stage2 Valet Mode v115.ptm

For vehicles experiencing underboost conditions, the following High Wastegate maps can be found online at

  • Stage2 91 v115 HWG.ptm
  • Stage2 93 v115 HWG.ptm


New Subaru Hard Parts

COBB TD05H-20g Turbocharger


The COBB 20G is an ideal turbo upgrade for those looking to increase the top-end power of their STI while maintaining low and mid-range response. Capable of producing 400hp and retaining excellent throttle response, the COBB 20G is a perfect turbocharger for street or track use!

For more information and ordering, visit the product page!


2015 Subaru STI Stage1+ Power Package

Stage1+ 2015 STI



Combine the worlds best selling, most flexible ECU upgrade solution with the COBB SF Intake/Airbox combo to give your 2015 STI more power and greatly improve driveability!

For more information and ordering, visit the product page!

Subaru SF Airbox Edge Trim and Trimlock

SF-Heatshield-Edgetrim_main SF-Heatshield-Trimlock_main

If the Edge Trim or Trimlock from your Subaru SF Airbox has been damaged or gone missing, we now have replacements available to get your SF Airbox looking new again!

2015 STI SF Airboxes use Edge Trim while all other Subaru SF Airboxes use Trimlock.

For more information and ordering, visit the product pages!

Edge Trim:


New GT-R 1/4 Mile World Record!

The ETS GT-R is at it again! The Accessport tuned Nissan re-takes the title as the fastest GT-R in the world through a quarter mile. The Extreme Turbo Systems GT-R bested the previous record set by the AMS Alpha Omega GT-R by more than two tenths of a second! Making this feat even more impressive is that the ETS GT-R is running the stock ECU. But then again, it is tuned on the Accessport!

EcoBoost Mustang Exhaust Update

If you’ve been keeping up with our R&D updates, you know that EcoBoost Mustang Hard parts development is chugging along.  A Stage 1 power package is just around the corner with additional stages coming soon!  Here’s a sneak peek at a our Turboback Exhaust which will be offered as a part of the advanced stage packages.

Mazdaspeed Updates : Engine On/Off Detection, Accessport Advanced Adjustments, Accesstuner Improvements


The COBB Mazda Expert Group has been working on a host of updates for this platform and excited to announce immediate availability of the following features!  Wastegate Duty Cycle, Flat Foot Shifting, and Launch Control adjustments can now be made utilizing the Accessport.  Previously, it was necessary to make adjustments using Accesstuner, these changes can now be made in-car!

Accessport Firmware Updates (

Engine On/Off Detection:

This feature, when enabled, allows the Accessport to power on when the vehicle is detected to be running and shut down once the engine has been turned off.  By default, this feature is disabled.  If you wish to use this feature, simply follow the instructions in the Knowledge Base article linked below!

COBB Knowledge Base : Enable Engine On/Off Detection

Accessport Advanced Tuning:

These settings will enable the ability to make minor adjustments to maps to enable Flat-Foot Shifting(FFS) and Launch Control(LC), as well as adjust Wastegate Duty Cycle.

Note: LC and FFS adjustments are only available on COBB v234 OTS maps (or higher) and Wastegate adjustments are only available on COBB OTS maps.  In order for LC and FFS adjustability to be active with a custom tune, maps will need to be resaved in Accesstuner Version (or newer)

By default, these features are disabled.  To enable Advanced Tuning Settings, follow the instructions in the Knowledge Base article linked below!

COBB Knowledge Base :  Advanced Tuning Settings

Off-The-Shelf Map Updates:

COBB Stage 1, Stage 2, and Stage 3 maps have been updated to v234 to support Advanced Tuning settings.

  • Stage1 v234.ptm
  • Stage1+ v234.ptm
  • Stage1+ with IC v234.ptm
  • Stage1+DP v234.ptm
  • Stage1+SF v234.ptm
  • Stage1+SF+DP v234.ptm
  • Stage2 v234.ptm
  • Stage3 v234.ptm

Non-Performance maps will remain at v233 (no updates)

Accesstuner BETA Updates (

The following changes have been made to Accesstuner as a BETA release.  In order to update to BETA software, launch Accesstuner and go to Help -> Updates -> Check for Updates.  Toggle the check box for “Beta Software”.

V3 Accessport Adjustments Compatibility:

Maps saved by this version of Accesstuner add compatibility for Accessport Advanced Tuning adjustments(LC/FFS).

  • Note: WGDC adjustments is only compatible with COBB v234 OTS maps

Steering Wheel Angle Sensor (SWAS) for Gen 2 Mazdaspeed3:

When traction control is turned off, these two toggles will eliminate torque reduction based off of steering wheel angles in first and second gear.

swas _toggles

Torque Reduction:

DBW Throttle A/B/C Compensation: These tables represent the amount of compensation, or correction made to the DBW Duty Cycle when torque limiting is requested.


Gen 1 Mazdaspeed3 / Mazdaspeed6 Shift Compensations (MS6 Stutter Fix):

Shift Timer – Shift timing delay based on gear.
ECT Based Shift Timer Compensation – This table enables/disables shift timing based on Engine Coolant Temperature.


  • USDM 2006-2007 MAZDASPEED6
  • USDM 2007-2009 MAZDASPEED3
  • WM 2004-2007 MAZDASPEED6 / Atenza / MPS
  • WM 2007-2008 MAZDASPEED3 / Alexa / MPS

Other Miscellaneous Accesstuner Updates:

Table Description Pane – displays description for selected table below the table list.


Other various improvements include improved Window Dialog Size, Undo feature, Direct Cell Edit, and Table Cell Selections.

COBB R&D Update : March 2015

February has come and gone, we’re hitting March with wheels turning!  Here’s a sneak peek at what our Engineering Department is working on this month!

2015 Subaru STI SF Airbox & SF Intake/Airbox Combo now available!!

The 2015 Subaru STI SF Airbox and Intake/Airbox Combo are now available from COBB Tuning!

2015 STI SF Airbox


The SF Air Box adds the benefits of a cold air intake to the outstanding performance of the SF Intake. The factory inlet directs cold air from the front grill to the SF Airbox, which encloses the SF Intake. Hot engine bay air that robs horsepower is prevented from entering the intake system to provide consistent intake performance. This unique design also separates rainwater from the intake air, eliminating the water ingestion issues that plague in-fender cold air intakes. This intake airbox is constructed of 16 gauge aluminum, consisting of a one piece surround, directional lid, stainless steel hardware and all the necessary components for a seamless install with OEM quality fit and finish.

Additional Info:


2015 STI SF Intake & SF Airbox Combo


This intake and integrated airbox looks great and has the combined benefits of a short ram intake and a cold air intake without any of the negatives.

This system utilizes several unique features in an effort to maintain optimal flow for performance while minimizing turbulence that can cause engine management problems. From a custom conical cloth air-filter element, we use a CFD-designed velocity stack leading to an unique air flow straightener grid. This straightener grid is specifically designed to smooth the incoming air flow as it passes the Mass Air Flow sensor for precise readings. This eliminates the “dead spots” experienced by other aftermarket intakes due to turbulence. No other aftermarket Subaru intake system utilizes these critical design elements.

In order to provide a system that looks as good on the outside as the technical advancements happening on the inside, we utilize a one piece design constructed from a high temperature plastic composite. Not only does this save weight compared to the previous metal design, the plastic composite material offers much better heat rejection properties that help keep intake air temperatures cooler. In contrast, intake systems constructed using metal castings or piping can actually retain underhood heat and in turn heat the incoming air.

The SF Air Box adds the benefits of a cold air intake to the outstanding performance of the SF Intake. The factory inlet directs cold air from the front grill to the SF Air, which encloses the SF intake. Hot engine bay air that robs horsepower is prevented from entering the intake system. This unique design also separates rainwater from the intake air, eliminating the water ingestion issues that plague in-fender cold air intakes.

Calibrations – All aftermarket intakes for 08+ Subarus require tuning in order to ensure the MAF sensor reads properly and the engine operates within safe parameters. COBB Tuning has you covered with Off-The-Shelf Maps for the Accessport, making it as easy as install, flash and go! Head over to the Subaru Accessport Map Database to view the full selection of SF Intake Maps for your vehicle.

Additional Info:

As always, supporting Off The Shelf Maps can be found at

Bucky Lasek’s “Subrina” STI Build

Bucky Lasek has been a customer of COBB Tuning for a number of years now.  A true gearhead at heart, he loves being behind the wheel and enjoys being able to blow off a bit of steam when necessary.  Being a driver for Subaru Rally Team USA, Subaru is obviously in his blood.  He recently paid our COBB Tuning SoCal shop a visit to bump up the power output of his 2012 STI.

Bucky’s goal with his 2012 STI was to show what the car is capable of with the budget of an average enthusiast in mind.  Simple is the name of the game here, every bolt-on part has a purpose.  The car is equipped with a coilover suspension kit, upgraded swaybars, and basic bolt-on performance pieces to increase airflow through the engine.  This is a car Bucky can take his kids to school in, enjoy a bit of spirited driving in the canyons outside of LA, or beat on at the road course.  He originally came in a few years ago to have the car custom tuned on the stock turbo utilizing the COBB Accessport.  The car made 321 hp and 364 ft/lb on a 50/50 blend of ACN91 and 100 octane fuel with an upgraded exhaust manifold, turboback exhaust, fuel pump, and intake.


Recently, Bucky approached us looking to step up the power of his STI.  The car already had great low-end torque, he was simply looking to add more mid and high-end power to back up that torque.  After a consultation with the crew at COBB Tuning SoCal, a short list of modifications was established to reach Bucky’s power goal.

All of that would be tied together with custom tuning on three fuel types – 91 octane, 91/100 octane blend, and E85.  With the convenience of the Accessport, Bucky is able to switch between these maps in no time at all depending on the fuel in the tank.

When all said and done, Jon Hebbeln of COBB Tuning SoCal was able to squeeze out 431 hp and 445 ft/lb with the new setup on E85 fuel.  For the every day driving on ACN91 fuel, the car is making 362 hp and 378 ft/lb and the 50/50 blend of 91/100 octane is putting out 385 hp and 406 ft/lb.  As you can see, with the addition of just a few parts, the car has really waken up.  The use of E85 allows a tuner to be much more aggressive with timing and boost.


Porsche Power : 997 Stock Turbo 60-130mph Record



The measurement of time it takes for a car to accelerate from 60mph to 130mph has become increasingly more popular over the past few years.  This method of measuring acceleration creates a real-world benchmark that can be exercised universally.

Recently, with the help of proTUNING Freaks and our Porsche Lead Calibrator, Mitch Mckee, Greyson was able to take his Porsche 997.1 Turbo from 60-130mph in just 5.9 seconds.  Mechanically, this car is equipped with an AWE exhaust, Porsche GT2 intercoolers, Injector Dynamics ID1000 fuel injectors, and upgraded turbo inlet pipes.  All of that is tied together with a custom tune by proTUNING Freaks on E85 fuel utilizing the COBB Accessport and Accesstuner software.

Below are the two V-box screen shots showing a 6.002 second and 5.978 second run.  The previous record for a stock turbo 997.2 was right at 6.4 seconds.

16374986520_99b1454450_o 16388234148_a5d0e7e247_b


For perspective, here is a list of 60-130mph times of some popular enthusiast vehicles (stock):

  • BMW E39 M5 – 14.3 sec
  • Mercedes E63 AMG – 10.93 sec.
  • Ferrari Enzo – 7.3 sec.
  • Mercedes SLR McLaren – 7.24 sec.
  • Porsche 997.2 Turbo (PDK) – 8.79 sec.

A more complete list of times can be found on

Congratulations to Greyson and Protuning Freaks!!




2015 STI Development : Staged Power Package Evaluation

2015 Subaru STIAs you may know, one of our public commitments following the release of the new 2015 model year VA-series chassis code Subarus (2015+ WRX and STI) was to thoroughly explore each platform and quantify our findings whenever possible.  Because the 2015 STI retained a very similar mechanical configuration to the 2008-2014 STI (GR-series chassis code), many in the community have anticipated that hardware and tuning options would be identical to the current offerings.  The idea behind our testing was to discard any existing assumptions about how the 2015 STI may compare to its older brothers and make sure that we are providing hardware and tuning solutions that exceed expectations.

Two of the prevalent issues with the GR series WRX and STI have been a “Boost Creep” problem and a fuel system that is at or beyond capacity on cars that are equipped with a turboback exhaust, especially when combined with an upgraded free-flowing intake.  This topic was previously discussed here: Subaru Tuning : A Quick Look into Boost Creep.

The key item of significance here: Airflow increases must be met by increases in fuel flow – AFR is a ratio air against fuel, by definition, and thus they must increase proportionally with each other.  We’ve previously explored how adding an intake increases airflow on the 2015 STI in a previous article, available here: 2015 Subaru STI Development Update – COBB SF Intake Testing.

COBB Tuning's 2015 STI undergoing dyno testing a COBB Tuning Surgeline in Portland, OR
COBB Tuning’s 2015 STI undergoing dyno testing a COBB Tuning Surgeline in Portland, OR

Goal:  Analyze fuel system performance when attempting to tune for a COBB Turboback Exhaust and COBB SF Intake System on a 2015 STI.  Will the factory fuel system be adequate to support this setup?

Vehicle:  COBB Tuning R&D 2015 STI (#2).  ~900 miles on odometer.  92 octane pump gas.

Method:  In order to gather numerical data for analysis, we collected datalogs from the car under wide open throttle (WOT) dyno runs, in the following tune/hardware configurations:

  • Stock (S#); Stock
  • COBB v340 Stage1 93 OTS (S#); Stock
  • COBB v340 Stage2 93 OTS (S#); COBB Turboback Exhaust
  • COBB v340 Stage2+SF 93 OTS (Experimental) (S#); COBB Turboback Exhaust + COBB SF Intake System

Conditions:  45-48 degrees F, Sea Level elevation.  COBB Tuning Surgeline, Portland, OR.

Background:  In general, while performing aftermarket tuning, a fuel injector is considered to be at their flow limits once reaching ~95% Injector Duty Cycle (IDC).  Beyond this, the amount of “off” or non-driven time for the injectors between injection events is inadequate for allowing the electrical coil within the injectors to fully discharge.  With this, the beginning of the next injection event comes earlier than anticipated, as the injector is already partially charged when the ECU begins driving it for the next injection cycle, and the net result is a flow non-linearity (usually demonstrated as a brief rich dip in air-fuel ratio).  After passing roughly 105% IDC, even with this rich-leaning non-linearity, the total window for injection in terms of time is now simply too short, and an inadequate amount of fuel is delivered to maintained the desired air-fuel ratio, so air-fuel ratios begin to go lean of targets.

What does this mean?  Past ~95% IDC, we mechanically lose control over fueling and air-fuel ratio will not be on-target.  Dangerous lean conditions will result past ~105% IDC.

Things to keep in mind:  Air density is a critical factor.  We intentionally tested in Portland winter months, where temperatures are cool and atmospheric pressures are high.  At elevation and high ambient temps, the concerns mentioned above become reduced as air mass is reduced.  Keep in mind, however, that it was still in the mid 40’s during this testing.   Injector Duty Cycles could easily be 5-15% higher if the testing were completed in a much colder area around the United States, such as New England, which has seen a long period well below frozen this winter.

Results:  OK, time for the relevant stuff.  This chart shows the logged Injector Duty Cycle during a full-throttle dyno run for each of the aforementioned configurations.  We’ve added a red line showing the 95% threshold we would ideally like to stay below.

Graph of Injector Duty Cycle (Y-axis) against Engine Speed (X-axis) for each configuration
Graph of Injector Duty Cycle (Y-axis) against Engine Speed (X-axis) for each configuration

As we can see, the issue is already borderline on the completely stock vehicle.  Subaru targets an extremely rich air-fuel ratio and the 2015 STI has been observed to be the most powerful STI to date; one has to wonder why they have not upgraded the fuel system’s capacity to match this.

With tuning (Stage1), we see that peak values are similar to stock.  We are targeting a leaner AFR but using more boost/airflow to make more power, so overall total injector usage remains similar.

At Stage2, we’re really getting up there.  The fully upgraded post-turbo exhaust hardware facilitates more airflow and we use even more injector as a result.  No NASA scientists needed on this one!  However, while Injector Duty Cycle does definitively now exceed 95% for a good portion of the run, it stays around 100% peak.  We have lost control of fueling, but we probably are not going to induce lean conditions yet, meaning the engine should not be at any significant new risk.

Stage2+SF: Uh-oh!  Now that the intake side has been freed up, we’re using a LOT more injector.  With Injector Duty Cycles peaking around 107%, we can no longer be sure that there is enough fuel available to keep a ball-park safe air-fuel ratio, let alone precise control over it.

As mentioned earlier, this would only get worse as ambient temperatures go further downwards.  While mid-40’s is definitely cold for all of the Arizonians reading along, Michigan residents are likely nodding along in full agreement.  Much of the U.S. sees sustained temperatures well below 40 F during their colder periods of the year.

Summary:  So, where does this leave us?  In short, it means that we (COBB Tuning Subaru Experts) are not comfortable offering “Stage2+SF” as a released stage package for the 2015 STI.  We know this is likely to disappoint some and confuse others, especially since the package is still offered for the GR vehicles.   However, not all is lost.  Thanks to our partnership with Injector Dynamics, we are well-positioned to now offer OTS packages that include fueling system upgrades, which have typically been “custom tune only” territory for Subarus.  Be on the lookout for an upcoming COMPLETE Stage3 package for 2015 STI that includes fuel system solutions in addition to full turboback and intake hardware!

COBB R&D Update : February 2015

Here’s a quick peak at what our Engineering Team is working on for February!  Big projects include Ecoboost Mustang Turboback Exhaust, 2015 WRX Intake/Airbox Combo, and a COBB Exclusive – Accessport adjustable Traction Control!