So I have a big problem when driving my car more than like 20 miles. The exhaust is just too damn loud.

I've got a 2012 with 6000 miles on it. Had all the stuff installed at 300 miles.
AEM Widemouth DP
Cobb HFC (catted testpipe)
Cobb 3" Quad tip cat back

I had a resonator put in a week ago a foot before the rear axle and that didn't help. In fact I think it made it a tad louder.

It's loud. It resonates. Even at idle it gives me a headache. But louder the higher RPM. I hate my car.
My ears ring if I drive it for any long distance. My DB meter app on my phone says 90DB at 80MPH in my car.

I already ordered a crapload of dynamat stuff, foam and mass loaded vinyl to soundproof my trunk and back seat area. It's not going to be enough though.

I'm this close to putting my entire OEM exhaust back on and get it retuned regardless of the HP loss.
Can anyone think of anything I can do short of that? Should I start swapping out pieces? Like just put on the OEM muffler and see if that helps at all so I know what the problem is? Will it even fit on the joint to the Cobb 3" long pipe after the cat? I don't feel like spending any more money on this literal headache.

Is it the high flow cat that's making it loud? Maybe the flex joint in the AEM DP?
From everything I've read, people say the DP and the muffler aren't loud parts.

Thanks for any insight you can provide on these parts or what could be causing it.

 

Personally I didnt find the Cobb exhaust to be loud at all when I heard it.. Either way you wont be able to tell much of a difference when it comes to adding a downpipe and a hfc. Ive had the AMS downpipe and there was no noticeable difference in sound. Ive also had a hfc on my old X and there wasnt a difference there either. Best bet would be to look for a different rear section that you can use with your mid pipe. Or put the stock one back on and just get an axle back.

 

Lol maybe you should've done some more research before you bought all of those items?

 

Thanks WW....
I actually did research every single part for months.
I listened to sound clips, did endless searches on these forums, talked to people that had them etc.

Nothing should be particularly loud in my setup. The cobb catback is actually one of the quietest aftermarket exhausts you can buy from everything I've gathered.

 

Make sure you don't have any leaks in the exhaust anywhere.

 

Swap out for the stock catback.. and then make sure its the Exhaust making the noise... Our engines r pretty damn noisy on Highway speeds

 

I can't help you, because the above is exactly what I would have suggested if you wanted to try to "save" the exhaust that you have. The fact that the resonator - which you put in exactly the correct location - did not help suggests to me that the wide-mouth downpipe has moved the optimal location for an extra resonator. You see, the location at which a resonator will have the best effects depends on the flow of the exhaust, mostly before that point. Normally, right before the rear axle is where you put an extra resonator, but all of the confirming data for this come from cars with OE-style downpipes.

 

Double check any bungs you may have had in O2 sensor holes in the downpipe/whatever are still in. I had a bung work itself out in my Evo 8 and it was loud as hell on the highway till I found it.

 

T1r 76s... love mine.

 

It's a little late for the OP, but I agree, hence:

 

lol i lost ssome hearing from my previous car so this makes me lol.

 

Thanks a bunch guys. Once again the Evo community is there to help me out.
I will try swapping back to the OEM muffler just to see if that fixes anything.

I don't think it's a leak, but I'll definitely have my shop recheck everything. It's louder the higher in RPM, but in general the decibel level is not as bad I think as just the resonance. Like the pulses of gasses at their certain frequency.
Something about the cabin amplifies this too. If I open my windows or sunroof it helps with the sound pressure waves or something.

I love the throaty sound. It's low and rumbly, but man that resonance sucks.
I don't think I'm just being a wuss about this. I've owned an Evo 8 before, and this one I had for 300 miles before the mods and had no problem with the sound.

Will keep everyone posted with the sound deadening too.

 

I'm surprised it's loud to be honest. usually with a larger muffler in the back (similar to stock) and a HFC the car is about as mellow as it can get with an aftermarket exhaust.

a few companies sell race mufflers, but we have never used them. It's an inline muffler that be added to the exhaust stream. The resonators don't do much in all honesty. I would even go out on a limb to say it makes the note deeper.

I would look at the following part numbers and see see if anyone has results.

1769 (Vibrant - 9" Long race muffler - 3" )
17695 (Vibrant - 5" Long race muffler - 3")

or look at a ultra quiet resonator, which is shaped like a mini muffler similar to what we use on our v2 rears to put in stream.

1142 (Vibrant resonator)

Thanks!

Michael

 

Drone is the worst, and not always easy to fix. I don't mind noise, but that resonating drone at cruise kills me too. I've messed with the Dodge turbo diesel and drone in the past and it was weird. I've taken off the cat, added a resonator trying to keep it nice and quiet, and had drone. Took off the resonator and left the cat off, and it was way louder, but the drone was gone. I've tried aftermarket exhaust systems, nice and quiet, but bad drone. Totally strait pipe, loud as heck, but nice down the highway. I really do believe that you added a muffler and the drone got worse, I've been there.

I'm not looking forward at all to messing with the exhaust on my car, 12 gsr, I'm really scared of cruising drone. But from the research I've done, and the reading between the lines, I'm gonna go single outlet exhaust. They seem to have a sweet spot between 70 and 75mph.

 

Ear plugs will help lol. But seriously, listen to ETS Michael they know their ****