The Nuclear Propulsion Package (NPP) option is a vacuum controled valve on the factory exhaust which is controlled by the ECU. It will open and close based on RPM and throttle position.
The valves will be open for the first two seconds that the car is started. It requires time for the vacuum pressure to build to close the valves. After that The operation of the NPP is normally closed, open on demand. Have someone stand behind the car and bring up the RPM to 3,500 and you should see the valves open. The butterfly operation is tied to the throttle position sensor and the RPM. It uses the throttle position to determine driver intent. Under normal operation the valves work as follows:
Below 30% throttle and 3,500 rpm the valves are closed. Above 30% throttle and 3,500 rpm the valves will open. Between 30% throttle and 80% throttle and above 3,500 rpm the valves are open. Above 80% throttle and above 2,800 rpm the valves are open.
Dual Mode Exhaust is a feature that allows your Camaro to stay within 'driveby noise' compliance. At 3500 RPM the valves auto bypass the factory mufflers to form a temporary straight back system which allows increased airflow at higher speeds.
A Borla "Axle Back" or rear section exhaust implies the exhaust system is located behind the vehicle rear axle . Most installations are completed in less than an hour and require no cutting of the factory system. A Borla Axle Back performance exhaust is a less restrictive aftermarket exhaust system that will improve the sound level both inside the cabin and exterior. Borla Axle Back exhaust systems use engine-specific (not universal) mufflers that are designed, tested, and optimized specifically for a particular year/make/model vehicle.
Improvements in sound and performance are accomplished by using a superior straight-through muffler design, mandrel-bent tubing, and the application of proper engine-matched tubing diameter. In some vehicles Borla offers multiple sound levels (Touring, S-Type, and ATAK®) to suite the individual driver's taste in vehicle sound. Borla also offers the Cat Back exhaust system which is located behind the factory catalytic converter.
Borla Axle Back systems replace the factory rear mufflers and exhaust pipe with an improvement in overall sound & performance to your truck, SUV, or car. Welded tips are standard on most systems running gas or diesel fuels.
Some of today's modern vehicles have a factory service-point in the exhaust system (flange or slip-fit) located in the exhaust tubing behind the vehicle rear axle. A Borla Axle Back performance exhaust system replaces the factory exhaust system (behind this service-point) following the same exhaust path and secured using the original vehicle hangers and rubber isolators.
Vehicles that don't have a factory service-point require “cutting" the factory exhaust system before installing a Borla Axle Back performance exhaust system. Borla includes cutting instructions and hardware to complete the installation.
Borla pioneered the use of aircraft grade 304 stainless steel tubing, a material with higher content of carbon & nickel that won't rust or corrode for automotive exhaust aftermarket.