[Checkmate1]

Bumping this thread for more feedback.

[1LE Red Dragon]

Originally Posted by Checkmate1

All,

I am trying to find the sweet spot with regard to in cabin sound experience and of course out of the tailpipes.

What is the best exhaust setup (that does not include headers) that gives one an eargasm inside and outside the car that includes the following -

- Stock NPP Axle back
- No Interior Drone

The headers route will most likely void my warranty which is a no go.

Let's discuss.

If your requirement is to keep the stock NPP Axle back. Then the only thing you can do is do the Borla 60606 midpipe with 2nd cat delete. That is what i have on mine. It has NO drone at all, in any mode or circumstance. It is slightly louder than stock, and in my opinion is the best setup for price and warranty friendliness.

You can make it super quiet in Tour, But bordering on sounding almost perfect in Track mode. Pull the fuse, and it will be perfect sounding, just cant go back whisper quiet by the touch of button.

If you want louder and deeper the Flowmaster NPP version would be my next choice, although about 2x the price of the Borla 60606.

Stage 3 option is Borla 60606 and the Flowmaster NPP axelback.


My $.02

[Checkmate1]

Originally Posted by 1LE Red Dragon

If your requirement is to keep the stock NPP Axle back. Then the only thing you can do is do the Borla 60606 midpipe with 2nd cat delete. That is what i have on mine. It has NO drone at all, in any mode or circumstance. It is slightly louder than stock, and in my opinion is the best setup for price and warranty friendliness.

You can make it super quiet in Tour, But bordering on sounding almost perfect in Track mode. Pull the fuse, and it will be perfect sounding, just cant go back whisper quiet by the touch of button.

If you want louder and deeper the Flowmaster NPP version would be my next choice, although about 2x the price of the Borla 60606.

Stage 3 option is Borla 60606 and the Flowmaster NPP axelback.


My $.02

Many thanks. This is the type of feedback I was looking for.

[jred2255]

Originally Posted by jvandy50

i only have one little clip testing the valves, I'd had the fuse out for awhile and just wanted to make sure we were completely done before i pulled it off the lift. i will likely make a thread when i can get some more video and experience, but if you want what i have now just lemme know.

What does pulling the fuse do?

BTW i am looking at Flowmaster American Thunder Axle Back with a Scavenger X pipe.

[jvandy50]

Originally Posted by jred2255

What does pulling the fuse do?

BTW i am looking at Flowmaster American Thunder Axle Back with a Scavenger X pipe.

It controls the NPP, without it they’re open all the time. I couldn’t handle the fact that it closed some even in track mode. When i want it open, i want it open. And now that i have my SW catback on, i think i probably wasted money on getting the NPP setup...right now I’m loving the noise so much I haven’t closed the valves since i installed it. Still nice to have it just in case though.

[Checkmate1]

Originally Posted by jred2255

What does pulling the fuse do?

BTW i am looking at Flowmaster American Thunder Axle Back with a Scavenger X pipe.

I've been looking into this as well. Does it drone?

[jred2255]

Originally Posted by jvandy50

It controls the NPP, without it they’re open all the time. I couldn’t handle the fact that it closed some even in track mode. When i want it open, i want it open. And now that i have my SW catback on, i think i probably wasted money on getting the NPP setup...right now I’m loving the noise so much I haven’t closed the valves since i installed it. Still nice to have it just in case though.

Got it. I've only driven my car a couple times but i figured the valves were still closing on me in track mode at times.

Originally Posted by Checkmate1

I've been looking into this as well. Does it drone?

I'm not sure about the drone. In Track mode i'll bet there is some, but everything i have read there is no drone in "stealth" mode. It's a weekend car for me so a little drone won't ruin things. Retaining the NPP is a big deal to me now, but chances are it will never go into stealth mode . Hoping to have the system by Friday, i will update with impressions asap.

[staples87]

The Borla ATAK catback went on the ZL1 yesterday with the secondary cats still intact. There's a slight rattle when turning, so I'm going to give it a few days of heat cycles then will adjust the clamps / pipes accordingly for clearance. I'm sure this is installation error as the 3" piping is a bit large under the car, so everything needs to align up perfectly.

Thoughts on the sound? It's AGGRESSIVE... but very daily drivable, if need be. Stealth mode sounds like Track mode with the stock NPP (maybe a tad quieter) and this morning's start up (Stealth mode) outside was not bad whatsoever. So far, no complaints from the neighbors.

In terms of drone, there really isn't any. A very minor hum (windows down) from the deepness of the sound, but to be honest, I can hear the tire noise over the exhaust when just cruising. She REALLY opens up over 3,000rpms. I had a group of people last night asking me to rev the car, so when I did, it scared the hell out of them and surprised me too. It was a lot of money, but overall I'm very satisfied and happy with the purchase. My only concern is going to be the Borla NPP valves and how they hold up against rattles, ect.

[Checkmate1]

Originally Posted by jred2255

Got it. I've only driven my car a couple times but i figured the valves were still closing on me in track mode at times.



I'm not sure about the drone. In Track mode i'll bet there is some, but everything i have read there is no drone in "stealth" mode. It's a weekend car for me so a little drone won't ruin things. Retaining the NPP is a big deal to me now, but chances are it will never go into stealth mode . Hoping to have the system by Friday, i will update with impressions asap.

Great! Cannot wait to hear your feedback!

[jred2255]

Got the Flowmaster installed this morning. Sounds great. IMO this is how it should have come from the factory. Plenty of rumble but not obnoxiously loud. I did NOT install the x pipe, it was held up in shipping and should arrive today. My thinking was I would put the x pipe on if i wanted it to be a little louder. I will drive the car a few hundred miles and make up my mind then. But chances are i'll have the X pipe installed for a little more sound.
Side note: While in stealth mode the valves rattle. I don't ever plan on running in stealth mode but regardless i will take it up with Flowmaster. Short vid below on a cold startup.

https://i.imgur.com/bPu8wJX.mp4

[jvandy50]

that sounds really good to me

[Stealth7]

As noted earlier: 3" SS Borla S Type! Gets rid of the Suitcase Muffler, crimped portion over rear axle and sounds awesome on throttle and relatively quiet when you want it to be! You really will not want the exhaust louder. Also retains the OEM NPP valves. I would not delete the secondary CATS/Resonators for sound, warranty, emissions and resale purposes.

[jred2255]

Well, i added the X pipe to the flowmaster system this morning. Sounds even better. Much deeper, more grunt. Definitely a different sound, i like it much better. I don't think it got much louder if at all, just changed the dynamic.

[gmw0181]

Originally Posted by Checkmate1

All,

I am trying to find the sweet spot with regard to in cabin sound experience and of course out of the tailpipes.

What is the best exhaust setup (that does not include headers) that gives one an eargasm inside and outside the car that includes the following -

- Stock NPP Axle back
- No Interior Drone

The headers route will most likely void my warranty which is a no go.

Let's discuss.

I have Stainless Works with NPP and I have no drone. I can drive with radio on and hold a conversation with no problems.