[kamakaziplayer]

I’ve been looking through a lot of threads and was kind of left with an impression:
Whenever an owner is asking for exhaust mods recommendations that won’t produce rasp, they’re hit with “single midpipe with resonator + high flow cats”. Which seems to be the consensus.

Currently my car is on a Valvetronic midpipe without a resonator. I’ve been looking into downpipes. Here comes my dilemma, will a non-res MP + high flow cats produce rasp?

Any DP suggestions that won’t produce an CEL? I’ve been looking at the AA GESI catted DP’s and ARM catted DPs. Any other options worth looking into?

Anyone with that combo have sound clips? But honestly from my limited experience videos online don’t do exhaust sounds justice.

Lastly, I hear that replacing the muffler with an aftermarket one isnt the best as the valve controller starts acting funny. Can anyone confirm/deny/provide insight?

[Chi58]

Originally Posted by kamakaziplayer

I’ve been looking through a lot of threads and was kind of left with an impression:
Whenever an owner is asking for exhaust mods recommendations that won’t produce rasp, they’re hit with “single midpipe with resonator + high flow cats”. Which seems to be the consensus.

Currently my car is on a Valvetronic midpipe without a resonator. I’ve been looking into downpipes. Here comes my dilemma, will a non-res MP + high flow cats produce rasp?

Any DP suggestions that won’t produce an CEL? I’ve been looking at the AA GESI catted DP’s and ARM catted DPs. Any other options worth looking into?

Anyone with that combo have sound clips? But honestly from my limited experience videos online don’t do exhaust sounds justice.

Lastly, I hear that replacing the muffler with an aftermarket one isnt the best as the valve controller starts acting funny. Can anyone confirm/deny/provide insight?

If you don’t want a cel
Go gesi, there are several different Axleback units on the market
The most common with valve
Issues are titanium systems. Some axleback use a spring style mechanism to open and close the valve these are more prone to rattle, and some use diffent style
c clips that have different tension preloads .

[Berzerker]

Originally Posted by kamakaziplayer

I’ve been looking through a lot of threads and was kind of left with an impression:
Whenever an owner is asking for exhaust mods recommendations that won’t produce rasp, they’re hit with “single midpipe with resonator + high flow cats”. Which seems to be the consensus.

Currently my car is on a Valvetronic midpipe without a resonator. I’ve been looking into downpipes. Here comes my dilemma, will a non-res MP + high flow cats produce rasp?

Any DP suggestions that won’t produce an CEL? I’ve been looking at the AA GESI catted DP’s and ARM catted DPs. Any other options worth looking into?

Anyone with that combo have sound clips? But honestly from my limited experience videos online don’t do exhaust sounds justice.

Lastly, I hear that replacing the muffler with an aftermarket one isnt the best as the valve controller starts acting funny. Can anyone confirm/deny/provide insight?

IMO the stock muffler is really good at removing drone and rasp through the system, even without a resonator. I would recommend only doing that last if you really want more volume and are ok with risking more drone.

I don't think the valve controller has issues, there's also ways to calibrate it for different valve setups.

[Info@mad-us.com]

Originally Posted by kamakaziplayer

I’ve been looking through a lot of threads and was kind of left with an impression:
Whenever an owner is asking for exhaust mods recommendations that won’t produce rasp, they’re hit with “single midpipe with resonator + high flow cats”. Which seems to be the consensus.

Currently my car is on a Valvetronic midpipe without a resonator. I’ve been looking into downpipes. Here comes my dilemma, will a non-res MP + high flow cats produce rasp?

Any DP suggestions that won’t produce an CEL? I’ve been looking at the AA GESI catted DP’s and ARM catted DPs. Any other options worth looking into?

Anyone with that combo have sound clips? But honestly from my limited experience videos online don’t do exhaust sounds justice.

Lastly, I hear that replacing the muffler with an aftermarket one isnt the best as the valve controller starts acting funny. Can anyone confirm/deny/provide insight?

Anytime you introduce a high flowing downpipe your risk of rasp goes up. A lot will depending on your valve settings and how much air you are giving to the stock muffler.


This is our midpipe but probably the best you will get as a before and after. Our Downpipes are 200 cell while the others on your list are 400+


Non res single midpipe and stock downpipe

Non res single midpipe and Mad 200 cell catted

[kamakaziplayer]

Originally Posted by Info@mad-us.com

Anytime you introduce a high flowing downpipe your risk of rasp goes up. A lot will depending on your valve settings and how much air you are giving to the stock muffler.


This is our midpipe but probably the best you will get as a before and after. Our Downpipes are 200 cell while the others on your list are 400+


Non res single midpipe and stock downpipe

https://www.youtube.com/watch?v=vnskIRl-iSY


Non res single midpipe and Mad 200 cell catted

https://www.youtube.com/watch?v=W47E4aGNX3Q

ty for the info n vids for comparison, much appreciated. Quick question whats the difference between 200 cel and 400 cel?

[mike@x-ph.com]

Originally Posted by kamakaziplayer

ty for the info n vids for comparison, much appreciated. Quick question whats the difference between 200 cel and 400 cel?

generally, the fewer cells you have the better the air flow. of course, the quality of the cats makes a big difference as well.

[kamakaziplayer]

generally, the fewer cells you have the better the air flow. of course, the quality of the cats makes a big difference as well.

does cell count affect CEL coming on?
I’m assuming cell count will also affect volume? less cells = louder?

[Info@mad-us.com]

Originally Posted by kamakaziplayer

does cell count affect CEL coming on?
I’m assuming cell count will also affect volume? less cells = louder?

Generally yes, a higher cell count will reduce more emissions but there is more to it than that like material, quality and core design.

More cells will directly affect volume.

We use a 200 cell for the best flow and a S wound core like the higher end Gesi cores but, i'm not 100% sure what their cell count is..

[mike@x-ph.com]

Originally Posted by kamakaziplayer

does cell count affect CEL coming on?
I’m assuming cell count will also affect volume? less cells = louder?

It depends; HJS cats are 200 but won't trigger the check engine light.
Most 300 CEL generic brand cats will trigger the check engine light.

The same applies to airflow and sound; a GESI cat is rated at 850 HP, which is more than what you would get from a generic cat.