Project Green Speed did not kill WRX tuning. It killed the old, easy recipe: bolt on an aftermarket j-pipe, flash a COBB Stage 2 map, suppress the emissions-related codes, and call the build done.
The Accessport still works. COBB still offers OTS maps, current Stage packages, CAN-based flex fuel systems, and custom tuning through its Protuner network. The difference is that the tune, vehicle, and parts list now have to match much more closely. If you are planning a WRX build in 2026, choose the supported calibration first and buy the hardware it requires second.
Quick answer:
- Current COBB OTS maps require the vehicle, fuel, and hardware specified in their map notes, including any listed exceptions.
- Current COBB WRX OTS maps do not support aftermarket downpipes or j-pipes.
- The current COBB Stage 2 path retains the factory catalytic hardware.
- Flex fuel has returned for supported VA and VB WRXs through CAN-based hardware.
- Custom tuning remains available through COBB Protuners, within the current software limits.
On this page
- What Is COBB Project Green Speed?
- What Did the 2024 EPA Settlement Change?
- Does the COBB Accessport Still Work?
- Can I Still Use Accesstuner?
- Can I Use an Aftermarket Downpipe or J Pipe?
- What About Catless Downpipes?
- What Happened To WRX Stage 2?
- Can I Still Use Flex Fuel?
- What Can Tuners Still Tune?
- What Parts Can I Buy Before Choosing a Tune?
- What Should I Do With an Existing or Used WRX?
- FAQ
- Choose the Tune Before the Parts
What Is COBB Project Green Speed?
Project Green Speed is COBB’s emissions-compliance program for its parts, OTS maps, and Accesstuner software. The changes arrived in stages, including the removal of maps with disabled emissions-related diagnostic trouble codes in 2021 and a major Accesstuner update in April 2022.
For a WRX owner, the before-and-after looks like this:
| Area | Old COBB path | Current COBB path |
|---|---|---|
| Downpipes and j-pipes | Aftermarket pipe plus a matching Stage 2 OTS map | Factory j-pipe for current COBB WRX OTS-map support |
| Emissions-related DTCs | Selected codes could be disabled in a map | Current Accesstuner software does not offer those adjustments |
| Flex fuel | Legacy VA kits used an analog TGV-related ECU input | Current kits send ethanol-content data through a CAN Gateway |
| Stage 2 | Commonly centered on an aftermarket j-pipe | Current packages use matched airflow, cooling, and boost-control parts while retaining factory catalysts |
That last point catches people out. A 2018 parts list can still look perfectly normal in a forum thread or used-car ad, yet have no current COBB OTS map or support path. The hardware bolting onto the car does not make the calibration available.
COBB’s Green Speed FAQ confirms that the 2022 Accesstuner changes did not remove maps already stored on an Accessport or alter how an existing map made the car run. They changed what could be created or revised with updated tuning software.
If a compatible legacy map is already stored on your Accessport, the Green Speed update does not delete it or stop the Accessport from flashing it. Affected downpipe, j-pipe, and Stage-package maps are no longer preloaded or available to download from COBB.
Keep a backup of the legitimate map for your exact car and hardware. A replacement Accessport will not include it, and a file from another car is not a substitute.
What Did the 2024 EPA Settlement Change?
Project Green Speed came first. The federal settlement made the compliance obligations explicit.
On September 16, 2024, the EPA and Department of Justice announced a Clean Air Act settlement with COBB. The settlement requires COBB to stop selling the affected defeat-device products, remove delete features from its software, and stop technical and warranty support for those products. It also allows COBB to continue selling tuners and software tunes covered by the required engineering evaluation and CARB Executive Order. The EPA’s COBB settlement summary provides the full compliance terms.
The settlement did not ban the Accessport. It narrowed what COBB can support around it:
- Discontinued downpipes and other affected products no longer receive COBB technical or warranty support.
- Current software cannot be used to create emissions-delete tunes.
- Current products and calibrations follow documented emissions-compliance paths.
Does the COBB Accessport Still Work?
Yes. On a supported WRX, the Accessport can still flash compatible OTS or custom maps, display live engine data, record datalogs, and read or clear diagnostic codes. Project Green Speed changed the available calibrations and tuning controls, not the basic job of the device. Our WRX Accessport guide covers the complete ownership path, including OTS maps, custom tuning, gauges, logging, and used-device checks.
Before buying a new or used Accessport, verify three things:
- The Accessport part number supports the exact model year and transmission.
- A used unit has been properly uninstalled from its previous car.
- The intended map supports every engine and airflow part already installed.
An Accessport being compatible with the car does not mean every COBB map is compatible with the car’s parts. Read the current map notes before flashing.
Can I Still Use Accesstuner?
New end-user access is not the normal route. COBB paused new end-user Accesstuner requests in April 2022, while previously approved users retained access under the terms described in its Green Speed FAQ. For a new custom tune, the COBB path is a Protuner.
This distinction matters when reading an old build guide. Instructions that assume you can download Accesstuner and edit a map yourself no longer describe the current onboarding path.
Can I Use an Aftermarket Downpipe or J-Pipe?
An aftermarket pipe can physically fit the car, but it is not part of the current COBB OTS-map path. COBB’s current WRX Stage packages and supporting calibrations retain the factory j-pipe and catalytic hardware.
Do not buy the pipe and assume a current COBB Stage 2 file will cover it. Give the tuner the exact year, transmission, market, and parts list first. If the build depends on an unavailable map or disabled emissions monitor, change the plan before ordering hardware.
For package-by-package detail, see the updated WRX Stage 2 kits guide.
What About Catless Downpipes?
Current COBB software cannot provide the catalyst-monitor and DTC changes a catless setup commonly relied on. On a street-driven WRX, removing required catalytic hardware also creates an emissions-enforcement and inspection problem. Keep the factory catalytic system when building around a current COBB map.
What Happened To WRX Stage 2?
Stage 2 survived, but its COBB meaning changed. That is why two WRXs advertised as “Stage 2” can have completely different exhaust hardware and tuning support.
As of August 2026, COBB lists these current approaches:
- 2015-2021 VA WRX: NexGen Stage 2 packages combine the Accessport with a supported intake, charge pipe, top-mount intercooler, and three-port boost-control solenoid. The factory j-pipe stays in place. COBB’s VA NexGen Stage 2 package page shows the current parts and map relationship.
- 2022-2026 VB WRX: COBB’s current top-mount Stage 2 package includes an Accessport, top-mount intercooler, charge pipe, intake tube, and high-flow filter. It retains the stock j-pipe and is currently listed for manual and CVT cars, although the exact map and emissions coverage still depend on model year. See COBB’s VB WRX Stage 2 package.
Another tuner or parts seller may still use Stage 2 to mean an aftermarket j-pipe and custom calibration. The label alone tells you almost nothing. Ask for the installed parts and the actual map requirements.
For the complete terminology breakdown, see what WRX stages mean now.
Can I Still Use Flex Fuel?
Yes. On the VA WRX, COBB’s legacy analog flex-fuel setup used an ECU input associated with the TGV system to carry the ethanol-sensor signal. It did not require removing the TGV hardware, but it did rely on a factory emissions-related input. Once Green Speed removed that tuning route, a new or revised COBB calibration could not use the old analog path.
The CAN replacement leaves that factory circuit alone. Its Gateway reads ethanol-content data, plus fuel-pressure data when that sensor is fitted, and sends it as CAN data that a supported ECU calibration can use.
| WRX application | Current COBB-branded support | Detail that matters |
|---|---|---|
| 2015-2017 VA, USDM 6MT | CAN Flex Fuel | Uses the early VA-specific Gateway harness |
| 2018-2021 VA, USDM 6MT | CAN Flex Fuel | Uses a different Gateway harness from 2015-2017 |
| 2022-2025 VB, USDM 6MT/CVT | CAN Flex Fuel | MY2026 US support is still awaiting updated emissions documentation |
| 2022-2026 VB, Australian market | CAN Flex Fuel | Separate Australian-market hardware and application list |
For either VA range, the basic upgrade includes the ethanol sensor and CAN Gateway hardware. The fuel-pressure sensor is separate unless the chosen bundle includes it, and COBB’s OTS maps require the complete configuration named in the map notes. The current kits are not legal for sale or use in California while CARB EO coverage is pending. Compare COBB’s 2015-2017 kit, 2018-2021 kit with fuel-pressure sensing, and 2022-2025 US-market VB kit.
COBB is not the only company selling compatible CAN hardware. Delicious Tuning’s CAN Flex Fuel Kit V3 is a third-party sensor and Gateway package for 2022+ VB WRXs, but it still relies on a COBB Accessport and compatible OTS or Protuner calibration. In other words, it expands the hardware choice without replacing the flashing platform.
Before ordering either brand, match the model year, transmission, calibration, fuel-pressure hardware, and emissions status. COBB compatibility alone does not establish California legality.
For a package-by-package comparison, see the WRX CAN flex-fuel kit guide.
What Can Tuners Still Tune?
COBB Protuners can still create custom calibrations for supported WRXs, but current Accesstuner software does not restore the emissions-related features removed by Green Speed. A custom tune can account for supported hardware, local fuel, and an individual car; it cannot turn an unsupported emissions-delete configuration into a current COBB-supported one.
Ask the tuner these questions before buying engine parts:
- Does your current COBB software support my exact model year and transmission?
- Which part numbers should I install, and which should remain stock?
- Is the calibration an OTS map, a pump-gas custom tune, or a CAN flex-fuel tune?
- What emissions documentation applies to those exact parts in my state?
- What should I preserve before a dealer ECU update or Accessport firmware change?
If you want to compare a laptop-based route, the WRX open-source tuning guide explains current VA and VB options separately from the COBB ecosystem.
If you already know you want a custom calibration, compare the logging and shop time involved in a WRX e-tune versus a dyno tune.
What Parts Can I Buy Before Choosing a Tune?
Buy the tune-sensitive parts after choosing the calibration. That includes the intake, boost-control solenoid, intercooler, turbo inlet, header, turbo, and j-pipe.
You can plan chassis and sound changes more independently:
- Catback and axleback exhausts that retain the factory catalytic system
- Suspension and brake parts with verified vehicle fitment
- Wheels and tires sized for the car, brakes, and intended alignment
- Shifter and interior parts matched to the transmission and model year
Once you choose COBB OTS, buy the complete supported package or follow the map notes exactly. Once you choose a custom tune, get the tuner’s approved parts list in writing first.
What Should I Do With an Existing or Used WRX?
If the WRX is stock
Choose a supported COBB package, a custom tune, or another platform before buying airflow hardware. A stock car gives you the rare luxury of choosing the path without first undoing someone else’s parts list.
If it already has an old j-pipe tune
Record the map name and tuner, save the full parts list, and confirm whether the factory j-pipe is still available. Speak with the tuner before updating firmware, uninstalling the Accessport, visiting a dealer for an ECU update, or changing any engine part. COBB says the Green Speed software update did not erase stored maps, but an old map with now-restricted features may not be editable in the same form.
If you are buying a modified WRX
Do not accept “Stage 2” as a parts list. Ask for the Accessport, calibration source, exact intake and exhaust hardware, recent datalogs, emissions-readiness status, and the original catalytic parts. A current NexGen package and a legacy j-pipe build need very different follow-up.
Use the complete used WRX and STI buying guide for the records, cold-start checks, test-drive procedure, and pre-purchase inspection that belong around this tuning audit.
If the car is registered in California
Verify CARB EO coverage for each exact part number and calibration. A product described as catted, 49-state, or emissions-tested is not automatically covered for California use.
FAQ
Did Project Green Speed kill WRX tuning?
No. WRX owners can still use supported Accessport maps, current COBB packages, CAN Flex Fuel kits, and Protuner calibrations. Current COBB WRX OTS maps no longer support the old aftermarket-downpipe recipe, and current Accesstuner software does not offer emissions-related DTC adjustments.
Can I still run a COBB Accessport on my WRX?
Yes, if your WRX is supported by the correct Accessport part number and you use maps that match your vehicle and parts.
Can COBB send me a map for an aftermarket downpipe?
Not with a current COBB OTS map. COBB’s current Stage packages and supporting maps retain the factory j-pipe. If your WRX already has an aftermarket pipe, give a tuner the exact parts and existing map details before changing the calibration.
Is flex fuel back for the WRX?
Yes, but application limits matter. COBB’s current VA release covers US-market 2015-2021 WRX six-speed cars. Its US-market VB product page lists 2022-2025 manual and CVT applications; MY2026 is still awaiting formal support. COBB separately lists Australian-market VB flex-fuel support through 2026.
Can I still pass emissions with a modified WRX?
The answer depends on the exact parts, calibration, readiness monitors, and local test. Before inspection, verify that required emissions hardware remains installed, the monitors have completed, and any CARB documentation covers the exact part numbers where applicable.
Is a catted j-pipe legal?
Not automatically. A catalyst being present does not establish federal or California compliance for the replacement pipe. Verify the exact part’s emissions documentation and local inspection requirements before installation.
Choose the Tune Before the Parts
The Accessport is still useful, Stage 2 still exists, and flex fuel is back. What disappeared is the freedom to mix old forum recipes with current COBB software and expect a matching map to appear.
Pick the calibration path first. Match the car, transmission, fuel, and every engine part to it. That order is less glamorous than opening a stack of boxes, but it is how you end up with a WRX that runs the way the parts list promised.