Exhaust mode
Melting Slicks
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From: Nevada
Racer
Joined: Feb 2001
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From: Henderson NV
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It's not that simple. In Track, the NPP valves are open all the time except in certain gears at speeds below about 36 mph. That's because the federal drive-by sound tests are done at 35 mph.
In Sport and Tour, the valves open and close based on multiple factors, including throttle position, speed, and maybe rpm and selected gear. Also, the valves aren't always open or closed. In sport, and probably tour, they can be partly open. If you switch modes while driving at a steady speed of about 50-55 mph, you can hear the difference between tour, sport and track. Unless, maybe, you have an automatic transmission.
In addition to the NPP valves behind the mufflers, there's another set of valves, generally referred to as AFM valves, ahead of the mufflers. Whenever the car is in V4 mode, the AFM valves close partway to keep the car from sounding like a Honda Civic with a fart can exhaust. When those close down, the exhaust will get quieter no matter what mode you have set. An with an automatic transmission, the car goes into V4 mode a lot.
In Sport and Tour, the valves open and close based on multiple factors, including throttle position, speed, and maybe rpm and selected gear. Also, the valves aren't always open or closed. In sport, and probably tour, they can be partly open. If you switch modes while driving at a steady speed of about 50-55 mph, you can hear the difference between tour, sport and track. Unless, maybe, you have an automatic transmission.
In addition to the NPP valves behind the mufflers, there's another set of valves, generally referred to as AFM valves, ahead of the mufflers. Whenever the car is in V4 mode, the AFM valves close partway to keep the car from sounding like a Honda Civic with a fart can exhaust. When those close down, the exhaust will get quieter no matter what mode you have set. An with an automatic transmission, the car goes into V4 mode a lot.
Pro
Joined: Apr 2006
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I set my exhaust to Track mode this weekend. Sounds great. Then, for comparison, I set it to "Auto." I couldn't tell the difference between Track and Auto when the car is in Sport mode. So I left it in Auto because it's loud when I'm in Sport, but quiet in Tour.