stealth exhaust with downpipe?

[2013R]

I have a lot of non-desirable size changes in my setup, due to 2018 and 2019 catbacks having different size piping.. My collection:

- 2018 catback cut before muffler section with a Vibrant resonator in it. (2.5" pipe)
- 2018 oem muffler section with chrome tips removed, raw tips. (2.5" pipe)
- 2019 catback cut before muffler section with stock resonator in it. (2.37" pipe)
- 2019 oem muffler section bone stock (2.37" pipe)

At least in USA, the ONLY muffler section which has wide MK7.5 tips plus 2.5" piping is the 2018 model. I would love to get my hands on an oem 2018 muffler which didnt have the chrome removed, so i could have a straight 2.5" system again, rather than a mismash.

I have pumped out the 2 parts above which had 2.37" pipe out to 2.5" pipe with an exhaust expander. So now, I can interchange any of the 4 pieces above in any combination onto my car.

 

[jimlloyd40]

According to numerous posts by members of this board, the stock muffler is not a restriction, even on a big turbo setup. The Magnaflow is a larger than stock, straight through tube with packing around it.
My system has an APR catted downpipe, a Vibrant resonator and a Magnaflow muffler, all of which are 3" straight through tubing.

If I add the stock muffler (which is not a restriction) after the Magnaflow muffler(which is even less of a restriction), what part will be a restriction?
The only negatives are additional weight and the possibility that it won't sound good, or the car burns to the ground in the exhaust shop.

I don't agree. I believe the stock muffler is a restriction albeit not a bad one.

 

[Desslok]

I don't agree. I believe the stock muffler is a restriction albeit not a bad one.

It appears to be designed much more for noise supression than performance and certainly looks like it would be a restriction. I Haven't seen any actual dyno results to show one way or the other.

 

[jimlloyd40]

It appears to be designed much more for noise supression than performance and certainly looks like it would be a restriction. I Haven't seen any actual dyno results to show one way or the other.

Anything you do to reduce restriction will help produce power but it's not a significant increase. Except if you install a catless DP. That's a pretty significant increase you'll feel.

 

[BippityBopMeUp]

According to numerous posts by members of this board, the stock muffler is not a restriction, even on a big turbo setup. The Magnaflow is a larger than stock, straight through tube with packing around it.
My system has an APR catted downpipe, a Vibrant resonator and a Magnaflow muffler, all of which are 3" straight through tubing.

If I add the stock muffler (which is not a restriction) after the Magnaflow muffler(which is even less of a restriction), what part will be a restriction?
The only negatives are additional weight and the possibility that it won't sound good, or the car burns to the ground in the exhaust shop.

I am in the same boat as you. What did you end up doing?

 

[Desslok]

I am in the same boat as you. What did you end up doing?

Nothing yet.

"Why do something today, when you can do it some other time" - Millard Fillmore
(actually it's my quote, but Millard Fillmore needs his name dropped on occasion)

 

[BippityBopMeUp]

Nothing yet.

"Why do something today, when you can do it some other time" - Millard Fillmore
(actually it's my quote, but Millard Fillmore needs his name dropped on occasion)

I’m actually going to a shop today and will ask their opinion.

Thinking about 2 things.

1: Keep vibrant resonator, magnaflow muffler, then reduce 3” to 2.5” pipe and stick on the stock muffler (essentially having a resonator and 2 mufflers)
Just wonder if its gonna sound weird or restrict too much.

or

2: Keep vibrant resonator and then reduce to 2.5” for the stock muffler (essentially one resonator after the downpipe and one muffler)

Either way I just want it to be near OEM quiet or even quieter.

I will update with what I go with.

 

[Desslok]

Don't know of anyone running option #1. Would like to hear what that sounds like. Option #2 will definitely be louder than stock.

 

[BippityBopMeUp]

Don't know of anyone running option #1. Would like to hear what that sounds like. Option #2 will definitely be louder than stock.

I ended up going with option 2.

I enjoy the sound that the vibrant produces with the stock muffler. Def quiet enough for my liking without the raspiness that comes with the stock resonator.

 

[jaystonewee]

I just finished building a custom mid-section for my 2018 GTI. I'm running an 034 cast downpipe, replaced the cat section with a GESI 400 cell Gen2, added a secondary Flowmaster 200 cell cat, v-banded to a Vibrant 17950, then reduced and v-banded to the stock GTI rear section/muffler with JST139 tips.

So far, it's super stealthy, barely louder than stock but 3" to the rear axle then 2.5" out. Once I get it dyno'd, I'll find out how "restrictive" it really is.

 

[Dalla GTI]

I ended up going with option 2.

I enjoy the sound that the vibrant produces with the stock muffler. Def quiet enough for my liking without the raspiness that comes with the stock resonator.

So your set up is/was aftermarket catted downpipe - vibrant resonator - stock catback/ muffler? I'm thinking of doing the same set up, I want it to be as quite as stock, I was even thinking of doing cts catted downpipe - vibrant resonator 2.5" - add a round vibrant muffler or the UQ vibrant resonator - stock muffler/ catback. Will that make sure it is as quite or quieter than stock or can I achieve what I'm looking for ( stock sound but with cts catted dp) with a different route?

 

[2013R]

I have had the perfect tone ever since i went back to the oem resonator. you can hear it in one of my last 5 videos when i had a drive. my setup front to back:

Ultimate Racing downpipe with ceramic cat.
Stock catback. (2018 with the 2.5" pipe)
(Black painted stock tips on muffler also).

Now some of my supporting mods also enhance the sound. (VWR intake, Turbosmart Plumb-back, EQT E30, etc..)

I have two changes i can make when i am in the mood. I have vibrant resonator which i can bolt in place of the stock resonator. (which makes it quieter and takes out some growl.) and i have a resonator pipe for the ultimate racing downpipe IF I wanted to use, it but i don't. PS, the catback resonator makes a bigger change in sound than my downpipe resonator does.

I also have a complete muffler from a 2019, but it has 2.37" pipe and doesnt mate to my setup. I think I have the oem chrome overlays cut off those tips.

 

[BippityBopMeUp]

So your set up is/was aftermarket catted downpipe - vibrant resonator - stock catback/ muffler? I'm thinking of doing the same set up, I want it to be as quite as stock, I was even thinking of doing cts catted downpipe - vibrant resonator 2.5" - add a round vibrant muffler or the UQ vibrant resonator - stock muffler/ catback. Will that make sure it is as quite or quieter than stock or can I achieve what I'm looking for ( stock sound but with cts catted dp) with a different route?

So your set up is/was aftermarket catted downpipe - vibrant resonator - stock catback/ muffler? I'm thinking of doing the same set up, I want it to be as quite as stock, I was even thinking of doing cts catted downpipe - vibrant resonator 2.5" - add a round vibrant muffler or the UQ vibrant resonator - stock muffler/ catback. Will that make sure it is as quite or quieter than stock or can I achieve what I'm looking for ( stock sound but with cts catted dp) with a different route?

Yes, the midpipe is still 3” from my aftermarket magnaflow exhaust and then the shop cut off the axleback portion and replaced it with the stock axleback. The shop flaired out the stock piping so that it would fit better with the wider midpipe. Its not the prettiest thing out there but It definitely is quieter than the magnaflow system when connected to the downpipe. No drone, a bit louder than stock while driving. Definitely works for me.

 

[Dalla GTI]

Yes, the midpipe is still 3” from my aftermarket magnaflow exhaust and then the shop cut off the axleback portion and replaced it with the stock axleback. The shop flaired out the stock piping so that it would fit better with the wider midpipe. Its not the prettiest thing out there but It definitely is quieter than the magnaflow system when connected to the downpipe. No drone, a bit louder than stock while driving. Definitely works for me.

Nice, thanks for the feedback, I'm definitely thinking of putting the vibrant resonator once I install the cts catted dp I'm just trying to figure out how I can make it even quieter.

 

[BippityBopMeUp]

Ive swapped out my turbo since making my last post about exhaust. Currently wanting to make it even quieter and am curious if adding one more muffler or resonator would help without messing too much with performance.