mine was $1,000

 

Agreed. First dealer I took it to wanted $1100 for the install. Got it done for $650 at another place.

 

If you want to install the exhaust yourself, go ahead and do it. Then take your car to the dealer for the valve relearn. Much cheaper that way. The Chevy dealer charged me 4 hours for the Borla S-type installation and included the relearn procedure. It depends which part of the country you live in but in Southern California the 4 hours labor cost was $740. Personally, the installation was a larger job than I wanted to tackle on my own so it was worth it to me to pay the dealer to do the whole thing.

 

Yeah, that's an option. I didn't ask for a price from the dealer for just the relearn, but they said they could do that. However, my wife has since stipulated that having the dealer install the exhaust was a requirement as she's seen me install too many exhausts in the past and oddly didn't want to see that again. I didn't think I was swearing that much...

 

Update: my Borla S-Type exhaust arrived on Friday as expected (thank you, FedEx!). I'm bringing the car to the dealership tomorrow to get it installed. They said it may be done tomorrow, but I should plan for picking it up on Thursday.

Prior to the C8 I had a 2015 Mustang GT for which I had purchased and used a Borla cat-back exhaust. When I put that car up for sale, I put the factory exhaust back on with the hope that I'd be able to sell the Borla. Well, I never listed it until Friday. It sold on Sunday for a cool $750. Nice chunk of change back and it's out of my shed!

I recorded some clips of the exhaust as is from factory (NPP). Of course everyone has heard that by now, but I'm hoping to record the same type of clips with the Borla installed for as much of a like for like comparison as possible. Interestingly, I thought the factory exhaust sounded louder and better in the videos than it does in person...weird, right? I'm looking forward to a smooth install and will get more clips recorded when I can. I go on vacation on Saturday so clips will have to wait until I get back. I'll post initial impressions to let you know what I think of it. I assume there'll be a break-in period where it gets louder. That seems to be true of all new exhausts.

 

At what distance is the 103 dB SCCA Race Car Sound limit measured?

 

OK, so my S-Type exhaust is installed and I have some initial impressions. It really does sound good! The tone is changed quite a lot with a very sweet sound that revs nicely with a lot of pops and burbles on over-revs. I'm a little surprised at the volume. I expected it to be substantially louder than factory, but it's not as loud as I thought it would be. I was concerned that it would be so loud that I'd never put it in Track setting anymore. However, while louder, I see no reason to stay out of Track for the exhaust setting in Z mode. This will work well for me as I didn't want it to get too crazy (I've made that mistake with previous cars).

I'll try to get some recordings together to match up with what I got with the factory system installed and do a little comparison. That'll have to wait for a couple of weeks as I'm going to be out of town for the next week and a half.

 

I upgraded to the Type-S over the NPP exhaust. It's a bit louder overall but especially when valves are open. It's most noticeable in 3500+ RPMs.

Burbles are more frequent & more profound. They are also noticeable in 1st - 4th gears vs just the first two with the NPP exhaust.

 

To those that have replaced their factory NPP exhaust, how are the NPP modules physically connected to actuate the internal flaps inside the factory exhaust system? If the factory NPP modules are physically disengaged from the exhaust, is there possibly a manual way to keep the internal flaps open? I'm thinking that by disengaging the factory NPP modules and replacing them using 3rd party NPP simulator modules to trick the car's computers, it might work. This way, I can get a louder volume from the factory NPP system. Does this thinking make sense to anyone else?

Can someone that has removed and still have their original NPP exhaust, with the NPP modules still attached, post some pictures to show the physical connections to the internal flaps? It will provide some insight to see if my idea is even doable before I start taking the rear fascia off. Thanks.

 

Sorry, I've been traveling. I can take a look at this and maybe get a few pictures for you. It'll probably be the weekend before I can do it, however.

 

@avigar I looked at my factory NPP exhaust this evening. All four valves (AFM and NPP) are spring-return to the wide open position. That is, if the actuators are removed (and you added simulators), you would not need to add anything to keep them open. That is their default location and will be kept there by fairly strong springs. Now, I don't know what that would mean for the AFM situation. If you kept the actuators in place for AFM and removed the actuators for NPP, that may be the way to get what you're asking about. Wide open all the time. I wonder how that would be. I guess like 'Track' setting all the time?

I took some photos and videos, but it was difficult to see much, but I can confirm that they spring-return to wide open when disconnected from the actuators.

 

@Monsoon Thank you for your response and confirming the open positions of the valves if the NPP actuators were disconnected. Based on your findings, I should be able to leave the still NPP modules mounted in place, but just electrically disconnected, correct? That should still keep the valves open? Thanks!

 

Well that's an interesting question. One thing I can't confirm is what the actuators do when they're disconnected. For all I know about that, they might spring-return in the opposite direction, I just don't know that. All I know at the moment is that the valves themselves on the factory NPP exhaust default spring-loaded to the wide open position. Since I had the exhaust installed by my Chevy dealer, I never saw the actuators disconnected or how they operate. I guess worst case you'd just have to remove the actuators and set them on a shelf somewhere. Seems like someone would have tried this by now.