[CWOFOR]

I have a 1SS with NPP; I just recently went over 4K on the mileage and have noticed difference in the exhaust note (louder). I started to notice it as I neared the 4K mark, up until then it was fairly quiet after I let off the throttle. Now, don't get me wrong, I like the sound, but, it is just a bit unusual that it would get louder all of a sudden.

Now my question for SS owners with NPP; is this normal?

[cmitchell17]

Now that you mention it, mine seems like it may be a little louder now. I'm pretty much convinced though that's its the placebo effect. Sometimes I don't like the sound since it seems like its to raspy and not smooth especially when you let off the gas. Other times I love it when you're riding around with the windows down in manual mode holding the gears.

Its just hard to believe they would make a stock exhaust this raspy? It also makes me think that the NPP in sport and track modes completely bypasses the mufflers? The rasp sounds like its coming from an exhaust with no mufflers, but I can't find any information about how the NPP works.

[SuperSound]

What Drive mode are you in? Do you have it manually set on Track for exhaust?

[CWOFOR]

Originally Posted by SuperSound

What Drive mode are you in? Do you have it manually set on Track for exhaust?

I'm in Touring mode, windows up (still chilly here), radio on. Everything the same as I usually do, but I can actually hear the car exhaust now; even at speeds of 25-35 mph. Like I previously said, just all of sudden, once I cleared 4K.

[Thatguy1]

Noticed mine got louder after 1500 miles. Here's the npp internals.

[Hard Parker]

Don't get headers then lol