How restrictive is the OEM factory active exhaust from the midpipes back?

[avora.RWD]

Hi. First post here. I have midpipes installed on my stinger with factory active exhaust and 3.3. I’m looking at getting primaries, but wondering if my stock cat back will be holding my power back. I was told by a shop that it should basically be straight piped from the midpipes back in sport mode, but I don’t believe that. Looks like it has the mufflers and another cat-looking shape in it, plus they’re just small pipes

 

[Ohiocruiser]

Who told you factory cat back was restrictive?

 

[oddball]

Every dyno result of exhaust modifications - at least for the original exhaust design. This is one of those situations where folks like Magnaflow actually aren't lying.
I don't know if anyone's bothered to compare to the active exhaust, especially with the bypass open.

Avora, right, on some cars the "sport" exhaust mode is straight through. But that's LOUD and tends to cause problems with law enforcement, so very few cars ever did that. So it still goes through a muffler, just it'll be a straighter path or less baffling, or something, that makes it a little louder. Is it appreciably less restrictive? Who knows.

 

[avora.RWD]

Who told you factory cat back was restrictive?

just intuition. basically this:

Every dyno result of exhaust modifications - at least for the original exhaust design. This is one of those situations where folks like Magnaflow actually aren't lying.
I don't know if anyone's bothered to compare to the active exhaust, especially with the bypass open.

Avora, right, on some cars the "sport" exhaust mode is straight through. But that's LOUD and tends to cause problems with law enforcement, so very few cars ever did that. So it still goes through a muffler, just it'll be a straighter path or less baffling, or something, that makes it a little louder. Is it appreciably less restrictive? Who knows.

I just hate the fact that I’ll have to pay nearly 2 grand to have a proper cat back and retain the valves. I definitely want that unrestricted twin turbo noise and spool though. I’ve considered just doing some custom work and keeping the valves since they’re past the muffler (i’ve checked) but I think the piping is so narrow it’ll sound raspy and awful catless

 

[Plakchup]

The one catback that becomes mostly straight pipe when you open the valve is the mbrp pro active if you look at how the valve is designed.

It's the design and setup I actually really like especially since it has a turbo style muffler, much smaller compared to something like what borla has for our cars. Valved exhaust setups are really great for daily driving. Most of the time when I am going to work I have my valves closed and it is far quieter than open but still has a really nice tone to it.

Yes it's not cheap but it's deep performance tone is really pleasing to hear. Borla tends to be bit raspier and has bit smaller pipe diameter (2.25" is borla and 2.5" is mbrp). If you thinking of doing an axle back delete or muffler delete I'll save you the headache. It is super drony and will annoy the crap out of you within minutes. The stock catback isnt necessarily garbage but it has very narrow crimmed down pipes right before the mufflers. It really sounds like a damn dyson vaccum though. The stinger can make good power still even with entire stock exhaust down after the primaries which are a pain to replace + requires a tune.

The mid pipe replacement is mostly for louder and more aggressive sound, very minimal performance gain. It does help the turbos spool up bit faster and yes it gets much louder.

So far the nicest sounding setup I've heard after trying out so many options is the mbrp pro active with ark downpipes. It is extremely loud though and has some drone/booming which does get less over time. It has a very exotic, deep performance tone kind of like a mini gtr in a way. But yes unfortunately not cheap, close to 2k. Best way to gauge an exhaust is to hear it in person and under load but not like evey corner there is a modified stinger.

If you want to hear my current setup give you an idea, link is below. I am not using the mbrp resonators. Tried them and they sadly killed the tone and volume far more than I liked. Hope that was helpful information! Good luck!

There is also a great video showing a pretty much stock stinger making nice gains with jb4 l: