[2SS Capt]

Originally Posted by SamSmoothCastel

California passed a law that an exhaust cannot be over 95 decibels. So unless you reside in this beautiful state leave the valves wide open.

Meh, I live in Kalifornia and I pulled my fuse, my valves are 100% open 100% of the time, if you don't jump on it, you are WELL below 95 dB...

Originally Posted by beowulf556

Are sport and track mode exhaust different? I thought they are both just fully opened all the time?

Even in Track Mode the NPP will close at certain RPM and throttle settings, the only way to have them open 100% of the time is either tune it that way or pull the NPP fuse (which is what I did) and they will stay open 100% of the time...

[arpad_m]

Originally Posted by beowulf556

Are sport and track mode exhaust different? I thought they are both just fully opened all the time?

They are different and neither commands the valves open all the time. There are separate tables in the tune that control valve positioning as a function of rpm and torque, and the contents of this table are different in each mode. As 2SS Capt said above, there is a small range within the track mode table (low load highway cruising) that instructs the module (not sure if it's the ECM or the FSCM / CCM, but one of the two) to close the valves.

[beowulf556]

Do the valves fully open when starting the car for a period of time?

[LT14EVA]

Originally Posted by beowulf556

Do the valves fully open when starting the car for a period of time?

If not in stealth then yes.

[LT4Greg]

Definitely in track mode they are open.

[jollymon]

Originally Posted by LT14EVA

If not in stealth then yes.

In my experience (2SS 1LE), even shutting down in "stealth" still results in next cold start with NPP valves open. = neighbors hating

What am I missing?

[arpad_m]

Originally Posted by jollymon

In my experience (2SS 1LE), even shutting down in "stealth" still results in next cold start with NPP valves open. = neighbors hating

What am I missing?

Unfortunately, stealth mode is not remembered across restarts. If you want to start the engine with the exhaust in this mode, you need to first turn the car on in accessory (or service) mode by pushing the button without holding the brake/clutch pedal, then switch the exhaust to stealth mode in the infotainment, and then start the engine.

If fast catalyst warmup is enabled in the tune (it is by default), you will still have a little bark in the first half second or so, but then the exhaust will immediately quiet down. I personally haven't seen a Camaro with this changed or turned off, so I don't know if it's actually possible to have a fully quiet cold start.

[CTRifecta]

Cold starts w the NPP exhaust are just the best.

[GroundhogSS]

Sport mode always and fuse F51 out to keep the valves open.

[MyNameIs]

Originally Posted by crisspy24

Is it bad to leave sport mode on all the time? Or leave it on while running errands in the city?

May cause cause additional tire wear.