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WRX Downpipe

Your WRX

Pick your year to see what fits.

This page covers the WRX and STI. The non-turbo Impreza has its own page.

+15–40 whp (est.)
Expert$720–$1,4003–6 hrs
All WRX mods

Why do it

The downpipe is the tightest part of the exhaust. A freer one helps the turbo spool sooner and make more power.

Heads up

Requires a tune. Check your local laws on emissions parts.

Tools you'll need

Starting out? See our budget tool list.

Parts to buy

Double-check fitment before buying. We may earn a commission when you buy through these links, at no extra cost to you.

Before you start

  • Catted parts are shown here. Removing or changing emissions parts can be illegal for road use, so check your local laws.
  • A new downpipe needs a matching tune before you drive hard.
  • Soak all the bolts and studs in penetrating oil and let the exhaust go fully cold.
  • Catted parts are shown here. Removing or changing emissions parts can be illegal for road use, so check your local laws.
  • A new downpipe needs a matching tune before you drive hard.
  • Soak all the bolts and studs in penetrating oil and let the exhaust go fully cold.
  • Catted parts are shown here. Removing or changing emissions parts can be illegal for road use, so check your local laws.
  • A new downpipe needs a matching tune before you drive hard.
  • Soak all the bolts and studs in penetrating oil and let the exhaust go fully cold.
  • Catted parts are shown here. Removing or changing emissions parts can be illegal for road use, so check your local laws.
  • A new downpipe needs a matching tune before you drive hard.
  • Soak all the bolts and studs in penetrating oil and let the exhaust go fully cold.
  • The old studs often break, so buy new studs and nuts before starting.
  • Catted parts are shown here. Removing or changing emissions parts can be illegal for road use, so check your local laws.
  • A new downpipe needs a matching tune before you drive hard.
  • Soak all the bolts and studs in penetrating oil and let the exhaust go fully cold.

Steps

  1. Remove the top bolts

    • Take off the intercooler and undo the top downpipe bolts at the turbo.
    Watch this step (on a 2006 WRX) (1:55–3:05)

  2. Remove the bottom bolts

    • From under the car, undo the bolts at the exhaust flange.
    Watch this step (3:05–3:58)

  3. Take the downpipe out

    • Work the old downpipe down and out.
    Watch this step (3:58–5:36)

  4. Move the O2 sensor

    • Move the O2 sensor to the new downpipe.
    Watch this step (5:36–6:23)

  5. Fit the new downpipe

    • Use new gaskets and bolt it up, starting at the turbo.
    Watch this step (6:23–7:53)

  6. Finish up

    • Refit the intercooler, then load your tune.
    Watch this step (7:53–9:00)

  7. Prepare the car

    • Raise the car on stands and let it cool.
    Watch this step (COBB, on an 08-14 WRX) (0:38–0:59)

  8. Remove the stock parts

    • Take off the parts in the way, starting with the intercooler.
    Watch this step (0:59–1:53)

  9. Detach the downpipe

    • Undo the turbo and exhaust bolts and bring the pipe down.
    Watch this step (1:53–2:32)

  10. Prepare the new pipe

    • Move your sensors to the new pipe and fit the gaskets.
    Watch this step (2:32–3:30)

  11. Fit the new downpipe

    • Bolt it up, starting at the turbo.
    Watch this step (3:30–4:12)

  12. Finish up

    • Refit everything, load your tune and check for leaks.
    Watch this step (4:12–5:03)

  13. Take apart the top

    • Clear the parts around the top mount intercooler.
    Watch this step (SubiSpeed, on an STI) (0:45–1:49)

  14. Remove the intercooler

    • Take the intercooler off.
    Watch this step (1:49–3:11)

  15. Remove the downpipe

    • Undo the bolts top and bottom and take it out.
    Watch this step (3:11–4:53)

  16. Fit the new downpipe

    • Move the sensors over, use new gaskets and bolt it up. Refit the intercooler and load your tune.
    Watch this step (5:36–7:39)

  17. Get ready

    • Raise the car on stands and let it cool.
    Watch this step (SubiSpeed, on a 2015+ WRX) (1:20–2:10)

  18. Remove the parts in the way

    • Take off the undertray, shields and sensor plugs.
    Watch this step (2:10–3:48)

  19. Remove the old J-pipe

    • Undo the turbo nuts and flange bolts and take it out.
    Watch this step (3:48–6:09)

  20. Fit the new J-pipe

    • Fit a new gasket and bolt it up.
    Watch this step (6:09–8:31)

  21. Finish the install

    • Refit the brackets and shields.
    Watch this step (8:31–9:40)

  22. Move the sensors

    • Move the O2 sensors to the new pipe and plug them in. Then load your tune.
    Watch this step (9:40–10:58)

  23. Prepare the car

    • Raise the car on stands and let it cool.
    Watch this step (Cameron Alford, on a 2022+ WRX) (1:19–2:33)

  24. Remove the factory pipe

    • Take off the rear section.
    Watch this step (2:33–3:33)

  25. Detach the J-pipe

    • Undo the turbo nuts and unplug the sensors.
    Watch this step (3:33–5:53)

  26. Remove the support bracket

    • Unbolt the bracket and take the pipe out.
    Watch this step (5:53–8:00)

  27. Fit the new J-pipe

    • Put it in with a new gasket and start the nuts by hand.
    Watch this step (8:00–9:32)

  28. Secure it

    • Tighten the nuts and refit the bracket.
    Watch this step (9:32–12:20)

  29. Finish up

    • Refit the sensors and shields, then load your tune.
    Watch this step (12:20–13:40)

How to know it worked

Did this guide work for you?

Safety first

  • Park on flat ground, set the parking brake and chock the wheels.
  • Never get under a car held up only by a jack. Use jack stands.
  • Let the engine and exhaust cool first.
  • Disconnect the battery before unplugging electrical parts.
  • Wear safety glasses.
  • If something doesn't match your car, stop and ask a shop.

Follow your part's instructions and your service manual's torque specs.