[shirtpants_]

It started out with me just doing the PE mod to my '11 n55 e90 335i.
That sounded great overall(loved driving with my wndows down), but just wasn't loud enough at WOT.

I bought a catless downpipe, and got a little too much of what i was asking for.
The car then sounded like a turbo diesel truck, had significant drone, rasped a pretty good amount, and seemed like it was more than twice as loud as before. It was embarrassingly loud, cold starts were brutal and just completely unacceptable when going to work at 6 AM.

About a month ago, I welded 2 vibrant resonators into the mid pipes right before the mufflers. It only got about 15% quieter, and the cold start noise level is tolerable. Now the rasp is all but gone, but so is the guttural growly sound of the exhaust. It just sounds airy and only has tone. I feel like The car sounds louder from 2500 RPM's than it does at 5,000 rpm. I also get a large amount of drone from about 1,900 to 2,900 rpm. I'm left with an exhaust that's too loud in everyday driving, and not loud enough when I'm higher in rpm's at WOT.
Is there anything else i can do to quiet down the drone/change the sound?
I actually avoid driving with the windows down now i dislike the sound so much.
Should I try to reverse the PE mod by just essentially drilling holes in the straight pipe in the muffler? Is it possible i have an exhaust leak somewhere that i'm not aware of?
I've already spent probably 600 dollars or so trying to get this car to sound right, and i really don't want to go any further modifying the stock exhaust if my only solution is aftermarket.

Right now I'm thinking if all else fails i'll try out the corsa mufflers. Anyone have any experience with these? They claim zero drone, but that may be with the stock downpipe, and I really don't feel like dropping 1k on some mufflers...

I've read that after a protune, or a different map on the JB4, people's drone went away. Would going protuned, coming from an ots cobb map help at all?

TLDR; I'm trying to get rid of 2,000-3,000 rpm drone after catless dp and resonator install. Wat do?


Link to corsa mufflers:
http://www.turnermotorsport.com/p-16...-mufflers.aspx

[Joey911]

Originally Posted by shirtpants_

It started out with me just doing the PE mod to my '11 n55 e90 335i.
That sounded great overall(loved driving with my wndows down), but just wasn't loud enough at WOT.

I bought a catless downpipe, and got a little too much of what i was asking for.
The car then sounded like a turbo diesel truck, had significant drone, rasped a pretty good amount, and seemed like it was more than twice as loud as before. It was embarrassingly loud, cold starts were brutal and just completely unacceptable when going to work at 6 AM.

About a month ago, I welded 2 vibrant resonators into the mid pipes right before the mufflers. It only got about 15% quieter, and the cold start noise level is tolerable. Now the rasp is all but gone, but so is the guttural growly sound of the exhaust. It just sounds airy and only has tone. I feel like The car sounds louder from 2500 RPM's than it does at 5,000 rpm. I also get a large amount of drone from about 1,900 to 2,900 rpm. I'm left with an exhaust that's too loud in everyday driving, and not loud enough when I'm higher in rpm's at WOT.
Is there anything else i can do to quiet down the drone/change the sound?
I actually avoid driving with the windows down now i dislike the sound so much.
Should I try to reverse the PE mod by just essentially drilling holes in the straight pipe in the muffler? Is it possible i have an exhaust leak somewhere that i'm not aware of?
I've already spent probably 600 dollars or so trying to get this car to sound right, and i really don't want to go any further modifying the stock exhaust if my only solution is aftermarket.

Right now I'm thinking if all else fails i'll try out the corsa mufflers. Anyone have any experience with these? They claim zero drone, but that may be with the stock downpipe, and I really don't feel like dropping 1k on some mufflers...

I've read that after a protune, or a different map on the JB4, people's drone went away. Would going protuned, coming from an ots cobb map help at all?

TLDR; I'm trying to get rid of 2,000-3,000 rpm drone after catless dp and resonator install. Wat do?


Link to corsa mufflers:
http://www.turnermotorsport.com/p-16...-mufflers.aspx

Hey,

Instead of welding on a pair of resonator, I put the secondary cat on from N54. Catless, and 335is mufflers.

My car drone in the same RPM range as you do. While my car was being protuned (eTune from PTF), the drone level varies through out the maps, and now my final map, drone is minimum and power is maximum

Do you still have your exhaust flap activated? With that, the drone heard by driver is way lower than open flap.

What I wanted to try is the center muffler from E90 N54s, to replace our xpipe.

Also, droning has a frequency, and out car has a piece of vibration absorber on the exhaust pipe, near the muffler. From memory, not 100% certain, at around 3000RPM, the measured f is ~130 - 135 Hz. N55 exhaust has a rubber of rating ~78 (again not sure). So I bought a piece of this absorber from a different model with higher frequency rating. And it did help with the droning/vibration caused by that specific frequency. I only got the ~100 rating one, couldn't find a 130Hz rating one.

N55 has a red one and N54 has a blue one. I hunted one down on eBay from an E46 with higher HZ rating for 20 bucks.

[Joey911]

Originally Posted by shirtpants_

It started out with me just doing the PE mod to my '11 n55 e90 335i.
That sounded great overall(loved driving with my wndows down), but just wasn't loud enough at WOT.

I bought a catless downpipe, and got a little too much of what i was asking for.
The car then sounded like a turbo diesel truck, had significant drone, rasped a pretty good amount, and seemed like it was more than twice as loud as before. It was embarrassingly loud, cold starts were brutal and just completely unacceptable when going to work at 6 AM.

About a month ago, I welded 2 vibrant resonators into the mid pipes right before the mufflers. It only got about 15% quieter, and the cold start noise level is tolerable. Now the rasp is all but gone, but so is the guttural growly sound of the exhaust. It just sounds airy and only has tone. I feel like The car sounds louder from 2500 RPM's than it does at 5,000 rpm. I also get a large amount of drone from about 1,900 to 2,900 rpm. I'm left with an exhaust that's too loud in everyday driving, and not loud enough when I'm higher in rpm's at WOT.
Is there anything else i can do to quiet down the drone/change the sound?
I actually avoid driving with the windows down now i dislike the sound so much.
Should I try to reverse the PE mod by just essentially drilling holes in the straight pipe in the muffler? Is it possible i have an exhaust leak somewhere that i'm not aware of?
I've already spent probably 600 dollars or so trying to get this car to sound right, and i really don't want to go any further modifying the stock exhaust if my only solution is aftermarket.

Right now I'm thinking if all else fails i'll try out the corsa mufflers. Anyone have any experience with these? They claim zero drone, but that may be with the stock downpipe, and I really don't feel like dropping 1k on some mufflers...

I've read that after a protune, or a different map on the JB4, people's drone went away. Would going protuned, coming from an ots cobb map help at all?

TLDR; I'm trying to get rid of 2,000-3,000 rpm drone after catless dp and resonator install. Wat do?


Link to corsa mufflers:
http://www.turnermotorsport.com/p-16...-mufflers.aspx

Oh yo you're the one who delayed and delayed his resonator installation!

Hello again lol

[shirtpants_]

Originally Posted by Joey911

[/INDENT]N55 has a red one and N54 has a blue one. I hunted one down on eBay from an E46 with higher HZ rating for 20 bucks

Huh, never heard of this before. where do you install it/take out the old one?

Originally Posted by Joey911

Oh yo you're the one who delayed and delayed his resonator installation!
Hello again lol

HA, yep we meet again. Still trying to find the secret to the catless daily driveable n55 that still sounds like it has some balls...
Glad you got rid of most of your drone, you were looking for that center muffler for quite a while.
Based on what you said ill probably try a protune from PTF first(I was headed that direction anyways), and then that rubber vibration absorber thing.

[Joey911]

Originally Posted by shirtpants_

Huh, never heard of this before. where do you install it/take out the old one?

HA, yep we meet again. Still trying to find the secret to the catless daily driveable n55 that still sounds like it has some balls...
Glad you got rid of most of your drone, you were looking for that center muffler for quite a while.
Based on what you said ill probably try a protune from PTF first(I was headed that direction anyways), and then that rubber vibration absorber thing.

Yeah so 4 things:

1: a tune(waste gate?). Dzenno at PTF like to say there's limited maps for N55 to fully customize everything, like idling and more. But my final map bs OTS, OTS drone so loud at the 2000 to 3000 RPM range, like a bass blasting, can't stand...

2: Exhaust pipe accessories.. 2nd cats, center muffler, etc...... I still think the center muffler is the shot for droning. Someone please sell me one already goddamn it.

3. Your stock flap helps so much. Keep it shut if it's too much.

4. Stock vibration absorber. I did this myself since I have tools, it's so accessible that I just need to lay down next to the wheel and do it. Try remove it, I bet it drone like a mofo.


I had my roommate hold his WRX throttle at his worst droning RPM while standing still, the measured frequency (using iPhone app) is same as driving (under load vs no load). I'm pretty sure you can measure your loudest drone RPM near the exhaust at around 3000, at round 133 HZ.

Other options, quarter wave resonator



PS: you guys should really get me a center muffler so I can report how much it helps with the freaking drone. Since no one ever report anything about using it to lower down the Catless noise.

[evo335xi]

I'm catless with corsa mufflers, should pop up on YouTube. Best sound, get many compliments. I've had loud cars from day one, car is perfect to me.

**have a 3.5 in downpipe and removed the secondary cats, that's when it became fun!

[KNAQ7]

If I were you, I would just switch back to an unmodified muffler and keep the DP. I run just a catless DP and the sound is pretty good, no drone on the highway and sounds pretty aggressive and growly.

[mashimarho]

I'm on the other side of the spectrum. I want my PE with dp a little more aggressive and louder.

[DK335]

Originally Posted by shirtpants_

It started out with me just doing the PE mod to my '11 n55 e90 335i.
That sounded great overall(loved driving with my wndows down), but just wasn't loud enough at WOT.

I bought a catless downpipe, and got a little too much of what i was asking for.
The car then sounded like a turbo diesel truck, had significant drone, rasped a pretty good amount, and seemed like it was more than twice as loud as before. It was embarrassingly loud, cold starts were brutal and just completely unacceptable when going to work at 6 AM.

About a month ago, I welded 2 vibrant resonators into the mid pipes right before the mufflers. It only got about 15% quieter, and the cold start noise level is tolerable. Now the rasp is all but gone, but so is the guttural growly sound of the exhaust. It just sounds airy and only has tone. I feel like The car sounds louder from 2500 RPM's than it does at 5,000 rpm. I also get a large amount of drone from about 1,900 to 2,900 rpm. I'm left with an exhaust that's too loud in everyday driving, and not loud enough when I'm higher in rpm's at WOT.
Is there anything else i can do to quiet down the drone/change the sound?
I actually avoid driving with the windows down now i dislike the sound so much.
Should I try to reverse the PE mod by just essentially drilling holes in the straight pipe in the muffler? Is it possible i have an exhaust leak somewhere that i'm not aware of?
I've already spent probably 600 dollars or so trying to get this car to sound right, and i really don't want to go any further modifying the stock exhaust if my only solution is aftermarket.

Right now I'm thinking if all else fails i'll try out the corsa mufflers. Anyone have any experience with these? They claim zero drone, but that may be with the stock downpipe, and I really don't feel like dropping 1k on some mufflers...

I've read that after a protune, or a different map on the JB4, people's drone went away. Would going protuned, coming from an ots cobb map help at all?

TLDR; I'm trying to get rid of 2,000-3,000 rpm drone after catless dp and resonator install. Wat do?


Link to corsa mufflers:
http://www.turnermotorsport.com/p-16...-mufflers.aspx

are you still running stock e90 mid pipes?
you could try installing an x pipe that is used on the e92's. i hear that running this setup full catless with vibrant resonators sounds perfect.

[winn3r]

Corsa mufflers is all you need to reach the sound you want.

[shirtpants_]

Originally Posted by DK335

are you still running stock e90 mid pipes?
you could try installing an x pipe that is used on the e92's. i hear that running this setup full catless with vibrant resonators sounds perfect.

Yeah, stock e90 mids. its just 2 straight pipes through from the downpipe to the resonators, then theres an H-pipe, then the mufflers... I actually started a thread a while back about the x-pipe vs H-pipe... I cant remember what the result was...

[shirtpants_]

Thought I'd update this thread

Got my tune sorted out with PTF, and the drone is pretty much gone. It's hardly noticeable now and not annoying to any extent, unless you're going uphill below about 2k RPM's. Hope that helps some of you out.

[Johnny Boost]

Originally Posted by shirtpants_

Thought I'd update this thread

Got my tune sorted out with PTF, and the drone is pretty much gone. It's hardly noticeable now and not annoying to any extent, unless you're going uphill below about 2k RPM's. Hope that helps some of you out.

Do you have the golf tee mod on? I have a similar set up and I leave the flap closed and there is 0 drone. IMO, it is the perfect set up for a daily driver. When I drive normally, it is somewhat conservative but during spirited driving, the exhaust note is nice and loud in the higher RPMs. If I feel like being obnoxious, I open up the flap and it's loud all the time. It's kind of nice having that control.

[Joey911]

Originally Posted by shirtpants_

Thought I'd update this thread

Got my tune sorted out with PTF, and the drone is pretty much gone. It's hardly noticeable now and not annoying to any extent, unless you're going uphill below about 2k RPM's. Hope that helps some of you out.

Yea nicely done

[Aaron@Autosource]

Check this out-
http://f10.5post.com/forums/showthread.php?t=1239526

[Joey911]

Is that the quarter wave length resonator? Open end works too huh