exhaust laws western australia

Exhaust laws in Western Australia are simple in theory: keep it legal under the Australian Design Rules, don’t make it louder than the factory limits, and don’t fiddle with emissions gear.

That means no gutted cats, no DPF deletes, and no “it’s not loud, officer, it’s character”—you can be defected and sent for a test if the car’s over the prescribed noise level.

Any exhaust mods must retain ADR compliance for noise and emissions, and substantial changes may need inspection or approval from the WA Department of Transport.

Side-exit party tricks and burble tunes that pop like a breakfast cereal can also get you pinged, especially if they raise noise or emissions.

If you want performance without the canary, keep the catalytic converter, use quality mufflers, and get it checked by a licensed workshop before the boys in blue do.