[jimmypop13]

Good afternoon! Just wanted to share my latest exhaust mods. So I had some Stainless Works headers, high flow cats, x-pipe(without the 2.5" inner neckdowns) and 3" afm valves, all running into the stock NPP muffler installed back in April. It sounded awesome and I loved that it's whisper quiet with the NPP valves closed because I can hold a conversation or listen to music with no issue but with NPP valves open, even though it is way louder than stock, I wanted something even louder. Well after looking at all the aftermarket axle-backs with NPP, I didn't like any of them for one reason or another. None seemed to give that whisper quiet mode with NPP valves closed and I didn't want to give that up.

So ultimately after considering my options, I decided why not bypass the muffler completely! I ordered some QTP electric cutouts with the wireless remote and had them welded in at the rear axle. You just hold the open or close button on the wireless transmitter for 5 seconds to open or close them and you can stop them anywhere in between if you want.





My installer and I were both shocked at how ridiculously loud this setup is now with the cutouts open. We had no idea the stock NPP muffler is doing so much muffling even with the NPP valves opened. With the QTP electric cutouts open, this thing sounds as loud as my 2002 Trans Am with open headers! It's shocking!

I made a few videos to show the difference.

Tour mode, NPP valves closed


Sport mode, NPP valves open


Sport mode, QTP electric cutouts open


Short WOT run with QTP cutouts open


Here are some revs with NPP valves closed, then open, then QTP cutouts open. The video doesn't do a good job capturing the true volume difference between NPP open and QTP cutouts open though. The difference is in real life is huge. QTP cutouts open is like 10x louder.


So I think I'm done with my exhaust for the time being. I love having the adjustability to have no one notice me and not upset the neighbors or draw attention, or I can be decently loud with the NPP valves open, or I can wake the dead with the cutouts open.

I just put on a roto-fab CAI so next step will be some tuning to dial everything in and tune out some codes i'm throwing for the high flow cats.
If you guys have any questions, just let me know!

[Sledgehammer70]

This is pretty amazing.

[Mighunter]

genius!!

[Emoto]

I would be interested to see if you do some dyno runs, what the effect of the open pipes do to your hp and torque. Might even be lower.

[Burly]

Very cool!

[MiamiBlueCamaro]

Short WOT video is craaaazy!

[V8SS]

That sounds amazing lol

[BradfordCamaro]

Spanky.

[SuperSound]

Wow, sound of pure anger there lol. I wonder what it would sound like with just the QTPs open with the stock tri-ys (and maybe the secondary cats deleted).

[Richard0nee]

Wow nice! That short WOT was awesome!

[jimmypop13]

Originally Posted by SuperSound

Wow, sound of pure anger there lol. I wonder what it would sound like with just the QTPs open with the stock tri-ys (and maybe the secondary cats deleted).

Me too. Someone should find out!

[jimmypop13]

Originally Posted by Emoto

I would be interested to see if you do some dyno runs, what the effect of the open pipes do to your hp and torque. Might even be lower.

I'm curious too. I did it more for sound than anything else. They are well back at the axle though so I wouldn't think it would lose anything. Most of the time when people lose torque it's from open headers.

I do plan on getting it tuned in the near future so I will try to do a run with cutouts open and closed and see what happens for ya!

[jimmypop13]

Originally Posted by Sledgehammer70

This is pretty amazing.

Thanks Sledge! I'm a big fan of your videos. You taught me how to properly jack up the car and change the reverse lights

I forgot to mention above that the one downside to this is its in front of the AFM valves so when v4 mode kicks in it sounds like poop. Really loud poop. Kinda funny though. I should get a video to show yall

[LibertyHill]

Giggling like a schoolgirl! Great job!