That explains it perfectly!
NPP Operation Specifics
Thread Starter
Melting Slicks
Joined: Jun 2009
Posts: 2,867
Likes: 66
From: . Wyoming .
NPP Operation Specifics
Finally, some specific information about using the NPP. This is from the Features Bulletin that Ken Fichtner is making available.
Exhaust Tailpipe Flow Control Valve System — RPO NPP
The exhaust tailpipe flow control system is used to tune the exhaust note for high performance vehicles. This vehicle is equipped with two tailpipe exhaust valves. One in the left tailpipe and one in the right tailpipe. Each exhaust tailpipe valve is installed in the low restriction exhaust path of a dual outlet muffler, near the exhaust tip.
When a tailpipe exhaust valve is open, the low restriction exhaust path is opened to the atmosphere, and the exhaust note becomes more aggressive.
An output circuit from the chassis control module is used to control the actuator that opens the left and right exhaust tailpipe valves. The exhaust flow control valve opens and closes when the chassis control module commands the actuator by pulse width modulation of the control signal.
To provide a more aggressive exhaust note when the vehicle is started, the exhaust tailpipe valves are opened during an engine crank event during specific modes of operation if that option is available. Once the engine is running, accelerator pedal position, transmission gear and engine speed are used to determine the commanded state (open or closed) of the exhaust tailpipe valves.
There are four specific exhaust performance modes that result in different behavior of the exhaust tailpipe valves. These modes are:
• Weather/Eco Mode: Exhaust tailpipe valves will be closed at all times when the engine is running.
• Tour Mode: Exhaust tailpipe valves are closed when the engine is idling and during normal/non-aggressive driving. Valves open during aggressive driving.
• Sport Mode: Exhaust tailpipe valves are open when the engine is idling and during most driving scenarios.
• Track Mode: Exhaust tailpipe valves are open at all times.
It is possible to personalize the exhaust sound. Select the Driving Mode menu and the following will be displayed:
• Exhaust
• Steering
Select Exhaust. This controls how robust or quiet the engine will sound. Select:
• Auto
• Stealth
• City
• Tour
• Sport
• Track
• Off
When the engine sound enhancement is turned Off via the personalization menu, the exhaust tailpipe valves will be put into track mode no matter which vehicle mode (Weather/Eco, Tour, Sport, or Track) is displayed on the drivers instrument panel.
This will be fun to play with.
The exhaust tailpipe flow control system is used to tune the exhaust note for high performance vehicles. This vehicle is equipped with two tailpipe exhaust valves. One in the left tailpipe and one in the right tailpipe. Each exhaust tailpipe valve is installed in the low restriction exhaust path of a dual outlet muffler, near the exhaust tip.
When a tailpipe exhaust valve is open, the low restriction exhaust path is opened to the atmosphere, and the exhaust note becomes more aggressive.
An output circuit from the chassis control module is used to control the actuator that opens the left and right exhaust tailpipe valves. The exhaust flow control valve opens and closes when the chassis control module commands the actuator by pulse width modulation of the control signal.
To provide a more aggressive exhaust note when the vehicle is started, the exhaust tailpipe valves are opened during an engine crank event during specific modes of operation if that option is available. Once the engine is running, accelerator pedal position, transmission gear and engine speed are used to determine the commanded state (open or closed) of the exhaust tailpipe valves.
There are four specific exhaust performance modes that result in different behavior of the exhaust tailpipe valves. These modes are:
• Weather/Eco Mode: Exhaust tailpipe valves will be closed at all times when the engine is running.
• Tour Mode: Exhaust tailpipe valves are closed when the engine is idling and during normal/non-aggressive driving. Valves open during aggressive driving.
• Sport Mode: Exhaust tailpipe valves are open when the engine is idling and during most driving scenarios.
• Track Mode: Exhaust tailpipe valves are open at all times.
It is possible to personalize the exhaust sound. Select the Driving Mode menu and the following will be displayed:
• Exhaust
• Steering
Select Exhaust. This controls how robust or quiet the engine will sound. Select:
• Auto
• Stealth
• City
• Tour
• Sport
• Track
• Off
When the engine sound enhancement is turned Off via the personalization menu, the exhaust tailpipe valves will be put into track mode no matter which vehicle mode (Weather/Eco, Tour, Sport, or Track) is displayed on the drivers instrument panel.
Thread Starter
Melting Slicks
Joined: Jun 2009
Posts: 2,867
Likes: 66
From: . Wyoming .
But if that's true, why have the Off setting when there is a Track setting, since Off=Track regardless of drive mode.
It's going to be fun to explore all these things. I just hope there is a master reset switch to put everything back to default.
Race Director
Joined: Sep 2013
Posts: 11,825
Likes: 2,474
From: Ft Lauderdale
Tech Contributor
I read this a couple times and realized I was gonna make it a lot harder than what I wanted. I'll just run in "Off" all the time so they are open around town, I don't plan on making huge burnouts to make a lot of noise, just want the idle/startup to be wide open. Then when I get up on the interstate for a long ride, I'll move to the tour position in the exhaust category to get a quiet ride.
Someone also posted here on his way home he thought the wide open NPP was quieter than he was expecting. I would like to hear from all the guys here that have taken delivery about how they like the car and it's features, rather than another pic of them waving....
Someone also posted here on his way home he thought the wide open NPP was quieter than he was expecting. I would like to hear from all the guys here that have taken delivery about how they like the car and it's features, rather than another pic of them waving....
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