Active Exhaust

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The Active Exhaust system allows the driver to choose between "Sport" and "Tour" modes.

  1. The "Sport" mode produces lower restriction to the engine, and will be noticably louder at lower RPMs.
  2. The "Tour" mode is quieter . . . up until approx 3000/3500 rpm at which time the computer opens the changeover valve, (temporarily switching to sport mode).

Sport Mode

If the dash switch is set to "Sport", then the changeover valve at large inlet to muffler is pulled open by the actuator motor and cable. All of the exhaust gases flow basically straight thru the muffler and exits on driver's side.

Furthermore, the valve is held open by the actuator motor and cable at all times.

Tour Mode

If the dash switch is set to "Tour" then the actuator motor releases tension on the cable, the spring will rotate the valve is closed. . . . This forces exhaust gases thru smaller tubing, baffles etc. in the muffler. Approx half of the gases will exit on driver side, and half will exit the passenger side. The valve will remain closed unless one of these three conditions occur:

  1. The dash switch is set to "Sport"
  2. The engine is above 3000/3500 rpm
  3. The engine is turned off

Active Exhaust Photo Gallery

Some diagrams from manual
Copied from Technical Manual
Cutaway of Muffler, showing internal flow, Sport
Cutaway of Muffler, showing internal flow, Sport
Cutaway of Muffler, showing internal flow, Tour
Cutaway of Muffler, showing internal flow, Tour
Photo taken in cold weather to illustrate the exhaust flow in Sport mode. High idle.
Exhaust in Sport mode
Photo taken in cold weather to illustrate the exhaust flow in Sport mode. Low idle.
Exhaust in Tour mode
Photo taken with driver rear wheel removed.
Valve plate position - Sport
Same as above, but tour mode.
Valve plate position - Tour
This article originated from a thread or post on 3000GT/Stealth International. (1809)