Replacing secondary cats with resonators?

[wootiown]

Hey folks! I'm craving an improved exhaust but I am BROKE and I also really don't want super loud exhaust. I'm mostly looking for marginally louder, deeper sound. Think factory Mustang GT exhaust or similar (yes obviously my V6 won't sound like a 5.0).

My buddy is learning to weld, and I'm considering the possibility of cutting out my secondary cats and replacing them with resonators.

I have a JB4 and I'd likely reach out to them to adjust the tune accordingly to prevent issues and CELs.

Anyone have any input on this? What resonators would you go with? Would this work or be a pain in the ass? Would my JB4 be able to prevent CEL issues, or would I need something to bypass the O2 sensors?

Thanks!

 

[Omega]

The car comes with stock resonators but if you want to upgrade to aftermarket I would get mbrp resonators. I also think you should add a x pipe while you are in there.

 

[Alpinesting]

yay! Anther idiot with a car that was never ment to have loud exhaust.

 

[wootiown]

yay! Anther idiot with a car that was never ment to have loud exhaust.

Huh? I explicitly said I DON'T want a super loud exhaust. Im still keeping my factory mufflers, I'm just interested in slightly improving the tone and volume since it sounds like an Accord rn.

 

[Alpinesting]

Sorry just an old man yelling at clouds. I just hear all the fart canned cars in the city and it is

nice to hear the burble instead. To each ther own. I apologize!

 

[rtv900]

I'm pretty sure the factory exhaust is galvanized steel dude, so your friend learning to weld is not going to be much help.
I'm not saying that can't be done. You could probably mig over galvanizing which would look like an absolute abomination and likely have leaks.
If it's tigged you'd have to grind off the galvanizing and then be left with paper thin steel that would be super hard to tig anyway.

If you seriously want to do this you'd almost have to just use band clamps and exhaust sealer to connect the sections.
Basically any way you do that it would be a hack job IMO.

bottom line is if you are broke it's pretty hard to modify a galv steel exhaust without ending up with a crap job on a nice car.
If it was stainless that would be totally different, would tig up nice, no coating to worry about, etc
but it's not

 

[blnewt]

Since you're on a budget and want a bit more volume this may check the boxes you're wanting for about half of what the ARK pipes cost.

DC Sports Midpipe Kia Stinger 3.3L (2017-2023) Genesis G70 (2017-2024) KMS1000

Fitment Information Kia Stinger 3.3L RWD (2017, 2018, 2019, 2020, 2021, 2022, 2023) Genesis G70 3.3 RWD (2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024) Does not fit AWD models Emissions Compliance This midpipe does not alter, replace, or modify any emissions equipment. However, this item does...

shop.redline360.com

 

[SRV]

I don't care how broke you are, do yourself a BIG favor and buy something you can bolt on/off as shown in post #7. And especially so since it sounds like your buddy's welding skills are not yet up to the task.

 

[BIG-D]

Secondary cats can be punched out in less than 10mins bro ...

And yes it does make it sound better.

 

[BIG-D]

 

[rtv900]

Secondary cats can be punched out in less than 10mins bro ...

And yes it does make it sound better.

it's pretty well known that punching out cats reduces performance unless you weld a pipe through the center so the inner diameter stays constant
otherwise it's horrible for flow to have a diameter increase and then an immediate decrease

 

[BIG-D]

Cool story bro... I have dyno sheets/dragy times and just a happy smile on my face in general that says otherwise...

 

[BIG-D]

Plus I solved my oil burning issue from running high flow cats all by myself no thanks to internet opinions, so I reckon I know what makes these things work and how to eliminate problems that cost $1000's to fix !

 

[rtv900]

Cool story bro... I have dyno sheets/dragy times and just a happy smile on my face in general that says otherwise...

wow, dyno sheets and dragy times? Awesome
Hammering out a cat and leaving a huge diameter increase that immediately goes into a decrease is the epitomy of grossly misinformed backyard hack job
People with even a moderate understanding of fluid dynamics just shake their heads when they hear nonsense like that

 

[BIG-D]

Someone out there has a better way of doing things... always.

Not everyone shares tho'

 

[rtv900]

Oh go in for dinner I think your mum is calling you... congrats you are number 3 on my block list

not surprised you have to block people as upset as you get
I'm picturing you with a flat brim hat tilted sideways, a vape pen in your hand and a can of NOS energy drink in the other

 

[SRV]

I have dyno sheets/dragy times and just a happy smile on my face in general that says otherwise...

Please show us the before and after dyno sheets and dragy times.

 

[rtv900]

Please show us the before and after dyno sheets and dragy times.

even if he actually had those, who knows how many other variables went into it.
If it was just a hack job punching out a cat while drinking Natty Ice in his back yard we all know the times would have gotten worse.

 

[SRV]

even if he actually had those, who knows how many other variables went into it.
If it was just a hack job punching out a cat while drinking Natty Ice in his back yard we all know the times would have gotten worse.

Well, let's see what he has.

Bragging about having 3 people on his block list is typically not a good sign though.

 

[rtv900]

Well, let's see what he has.

Bragging about having 3 people on his block list is typically not a good sign though.

watch out man, it's about to be 4