[z28pat]

I’m wondering if anyone here as kept the npp muffler with long tubes and how is it ? Is there drone ? What headers did you get and did you pick up power despite the stock muffler ?
Thank you

[KingLT1]

It's been done many times. Aftermarket exhaust is purely for sound. There is no power to be gain by changing anything from the secondary cats back. The only down fall to Headers with the stock NPP is rasp. Stock suit case muffler gets raspy with cat deletes and/or Long tube headers.

[Juiced1]

We see a lot of builds like this. Power gains are still solid with any long tube. I personally love the sound too. Not over the top but aggressive enough and no drone with the valves closed.

[z28pat]

Right now I’m in the planning stages because of the warranty and needing a tune with the lts. After that’s it’s game on!

[Agent K]

Originally Posted by KingLT1

It's been done many times. Aftermarket exhaust is purely for sound. There is no power to be gain by changing anything from the secondary cats back. The only down fall to Headers with the stock NPP is rasp. Stock suit case muffler gets raspy with cat deletes and/or Long tube headers.

What he said. That's why I customized my catback while keeping my stock NPP muffler. Now no rasp and no drone.

[TJay74]

I have been on catless ARH full length header system into the stoc NPP for over 2 years now, zero drone at all no matter what RPM or cruising speed. Just the pure bliss of the screaming Eagle's being released when I got WOT.

[z28pat]

I’m concerned about the rasp, how did you guys combat that and do you have any videos of your sound ? Thanks for the help !

[Walt.v]

Currently have American Racing Headers with my stock NNP Mufflers, at first I hated it cause of the raspyness at lower RPM's but when you punch it and hit higher RPMs it sounds SOO GOOD! And TBH with headers the active exhaust feature does not make a difference with quite to sport/track mode.

(ARH.No cats.Xpipe. Stock 1LE NNP Mufflers)

No drone.
Light Raspy noise at lower RPMs when coming in and out of gear.
Sounds like a beast at HIGH screaming RPMs

[Agent K]

Originally Posted by z28pat

I’m concerned about the rasp, how did you guys combat that and do you have any videos of your sound ? Thanks for the help !

Here's mine. But keep in mine this is custom. You'll have to get a sound clip from Walt.v for a regular set up.

https://youtu.be/ApkS2lkjMmM

[KILLA BEE]

Originally Posted by Agent K

Here's mine. But keep in mine this is custom. You'll have to get a sound clip from Walt.v for a regular set up.

https://youtu.be/ApkS2lkjMmM

I had it sounded perfect with my kooks
BUUTTT NEEDED MORE NOW HAVE BORLA

[z28pat]

Originally Posted by Agent K

Here's mine. But keep in mine this is custom. You'll have to get a sound clip from Walt.v for a regular set up.

https://youtu.be/ApkS2lkjMmM

Thank you , do you still have the front cats ? Sounds good , too much crackling for me though.

[Agent K]

Originally Posted by z28pat

Thank you , do you still have the front cats ? Sounds good , too much crackling for me though.

Yea, I still have my cats...they're somewhere in my storage shed.

Can't ever have too much crackle and pop

[jorgesvlog]

I have the Speed Engineering 1 7/8 long tubes with their catless x pipe bolted to the stock npp axleback and love it zero drone when in tour mode but boy does it wake up and get loud in sport or track!