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3 Inch exhaust: how to get it more quiet?

The 3 inch system looks like this:

-No cat

Why? it is stupid to believe you gain 1HP without a cat. The crappy original stuff will reduce the power, buuuuut: A good cat made of metal and with a good geometry at the entry and the out will reduce over 95% of pollution and won't cost any power.....and reduce noise


"You could put in a cat, put in more bends, or put in a bigger/better muffler."

This, two bends at the tail pipe, two times 90? and the car is quiet, ok a lot of less drone.


Regards, Kay
I agree.
I will add another vote for ?bigger is better?.
 
The 3 inch system looks like this:

-No cat

Why? it is stupid to believe you gain 1HP without a cat.

Maybe, like me, he is tired of expensive, but poorly made cats that last at most 2 years as an emissions reducer and at worst, begin to clog or break up under high temps. I had to resort to removing my cat, EXCEPT for emissions testing, if I didn't want to buy a new one for EVERY emissions test. Glad I'm no longer in Calif.
Dave B.
 
Do you know if the heat insulation wrap helped reduce in-cabin noise or is it's only value for thermal?

MagnaFlow 12219 and MagnaFlow 11249 are what I have on my GLH, they are the biggest that fit my car. Quiet and no drone.
Not cheap, but worth every penny to my ears.

muffler1.jpg
 
Bumping Sjeng's old thread..... I now have his same conundrum. Made my first 30 mile interstate run @ 70mph (around 3200R with the 4.10 final gear) and the exhaust droning made me wonder if an exhaust weld had broken!

I have a nice 3"DP with flex, V-banded to the 3" aftermarket CAT (probably the one Dave B. had fail, or similar), and then stainless Flowmaster transitioned to connect to my original TME rear muffler. Prior to my changes, I had a stock 9 series DP and factory CAT, followed by the TME system.....and the sound was sweet to me old ears. The aforementioned changes have turned the sound quite nasty. Sounds like I'll be investigating at least one MagnaFlow Oval aft of my CAT..... if not a pair of them with full 3" as Tryingbe did on his GLH.

I'll add a pic or two of my system from DP back, for TB posterity......






I want the power AND quiet.....this is my work car!
 
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I'm running a 3" back on my 240, and it was loud with the B21+T...but it's so much worse with the B6304. I'm catless (but will be adding one) with a magnaflow round can as a resonator pre-axle, and another magnaflow round can as a muffler in the stock location. I'm seriously tempted to make a baffle for the tailpipe like the hotrod or harley guys use on their cars, or swap out one of the straight through cans for a baffled muffler.
 
Maybe, like me, he is tired of expensive, but poorly made cats that last at most 2 years as an emissions reducer and at worst, begin to clog or break up under high temps. I had to resort to removing my cat, EXCEPT for emissions testing, if I didn't want to buy a new one for EVERY emissions test. Glad I'm no longer in Calif.
Dave B.

I think I've posted this before, but here's precisely what I used for years. The cat worked great since it was only used for one day every couple years. 10 minutes to swap. Last cat I ever had to buy.
https://www.atpturbo.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=tp&Category_Code=MDP
 

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Bumping Sjeng's old thread..... I now have his same conundrum. Made my first 30 mile interstate run @ 70mph (around 3200R with the 4.10 final gear) and the exhaust droning made me wonder if an exhaust weld had broken!
{SNIP]
I want the power AND quiet.....this is my work car!

Also, years ago I installed a 3 inch simple straight thru glass pack, around 18 to 24 inches long, to the rear of the cat location and it helped reduce the drone.
Similar to this.
Dave
.
aph-301211s_ml.jpg
 
I have true duals on vw v6 but it has 2 vibrant resonators and 2 long oval magnaflows with dual tips...sounds real low and doesn't get crazy annoying loud. Magnaflows can be spendy but they sound reeeeal nice
 
Bumping Sjeng's old thread..... I now have his same conundrum. Made my first 30 mile interstate run @ 70mph (around 3200R with the 4.10 final gear) and the exhaust droning made me wonder if an exhaust weld had broken!

I have a nice 3"DP with flex, V-banded to the 3" aftermarket CAT (probably the one Dave B. had fail, or similar), and then stainless Flowmaster transitioned to connect to my original TME rear muffler. Prior to my changes, I had a stock 9 series DP and factory CAT, followed by the TME system.....and the sound was sweet to me old ears. The aforementioned changes have turned the sound quite nasty. Sounds like I'll be investigating at least one MagnaFlow Oval aft of my CAT..... if not a pair of them with full 3" as Tryingbe did on his GLH.

I'll add a pic or two of my system from DP back, for TB posterity......



I want the power AND quiet.....this is my work car!

Hey DET17,

I ended up buying the magnaflow recommended on the previous page.

I run only one muffler at the back, and it sounds sporty but no drone at all.
Highway driving is still pleasant, as my car is a daily.

It is relatively expensive but worth every penny.
 
On one of my 240s I use one glasspack like Dave mentioned and one magnaflow. Not too loud at idle. Acceptable tone on highway as well.
 
Not sure what the IPD set up uses - installed the full turbo back exhaust a while back and while initially I found an issue with the "drone" I've either gotten used to it or it mellowed after it broke in.

The sound isn't problematic at all. Recently spent a day with my boss in the car and he never even mentioned it.

Also interesting to note how they go from 3" to 2.5" further back in the exhaust due to the density of the exhaust cooling further down the run.

Their cat and related muffler work well IMO (though that 4" tip is pretty ridiculous), I don't know what they are but that can't be too hard to figure out.


<iframe width="560" height="315" src="https://www.youtube.com/embed/RiDTsHYD-WY" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
From my experience the wrap help with higher frequency "ring" sounds, especially with steel exhaust parts.
 
Magaflow and a Resonator on the son's '92 940T. The tailpipe has also been bent to look stock. It's quiet in the cabin with no drone. Behind the car, you feel the exhaust more than hear it.
 
Magaflow and a Resonator on the son's '92 940T. The tailpipe has also been bent to look stock. It's quiet in the cabin with no drone. Behind the car, you feel the exhaust more than hear it.

If you know the PNs for each, please share. I'll be going under the car this week to get some dims and see if a Helmholz resonator will fit.... as well as other style resonators post cat.
 
Just want to add that you should never use baffled mufflers on turbo cars, it's a fairly well known thing. If you read the fine print on any of them it states this. I've been using Cherrybomb Vortex mufflers, cheap, and full size, thick steel that doesn't rot out like Magnaflow (my last Magnaflow lasted about 3 years) and they don't drone.
 
I just talked to my muffler shop. If you were around Rochester NY, I recommend them. Great CAR guys. Not just mechanics.

I have to correct myself, it was a stainless steel brand the shop uses, Xlerator, not a magnaflow. He thinks we didn't do a resonator. (They also did my 760 GLE V6, about a month later -- it gets confusing). They use a 2.5" I/O version, P/N XS1226. Summit carries them, and they show 3" versions.

BTW, my son pulled out a audio spectrum analyzer app when his 940T and my 760V6 were idling next to each other. Both show peaks below 100 Hz. His is lower (1 piston firing per rpm) than mine (1.5 pistons firing per rpm). His has no drone inside, mine has some, and I wonder if it the difference between his coming out at the back right corner of the car (like stock), and mine coming straight out.

Oh yes, another trick I learned on my WRX was using a turndown tip. It points the exhaust at the road and seems to quite things a little.

Good luck.
 
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