Anyone Running Headers, X-pipe and Powerloops?

[3002 tii]

Looking for feedback on anyone with a similar exhaust setup:

• Stock airbox preferably
• Euro (catless) headers
• Catted section 1 (modified US, OEM Euro, DKF 100/300)
• Supersprint section 2 x-pipe (or RE, BMS)
• Supersprint Powerloops (or Stromung)

The Powerloops are the one piece that I’m trying to isolate since that’s the biggest variable but I’ve heard the Stromungs are very close in volume and tone. My questions are:

1. Do you own a coupe or roadster? If roadster, please let me know how the answers below may vary depending on top up/down. And stock or aftermarket airbox?

2. How is the drone with and without the factory resonated section 2 x-pipe?

3. To the extent drone occurs, at what rev range does it occur? If it occurs regardless of x-pipe choice, does the x-pipe shift when the drone occurs?

4. Did the x-pipe affect hp/tq? If you have dyno to back up, while leak numbers may be same, how about the delta in low to mid range?

5. Any sound or video clips from interior/exterior?

[Z4M85]

This is very close to the setup you are looking for. Great tone without being loud and it allows all the induction noise to be heard from the airbox. It has a Stromung muffler, but those seem to be pretty similar in terms of sound and tone to the SS power loop or the SS street for the E46 M3. In another video with the car, the owner states that it has SS part/s on in it, so I am assuming it has the SS x-pipe, and since it is a euro car, it probably has the euro headers and cats.

[maupineda]

Originally Posted by 3002 tii

Looking for feedback on anyone with a similar exhaust setup:

• Stock airbox preferably
• Euro (catless) headers
• Catted section 1 (modified US, OEM Euro, DKF 100/300)
• Supersprint section 2 x-pipe (or RE, BMS)
• Supe rsprint Powerloops (or Stromung)

The Powerloops are the one piece that I’m trying to isolate since that’s the biggest variable but I’ve heard the Stromungs are very close in volume and tone. My questions are:

1. Do you own a coupe or roadster? If roadster, please let me know how the answers below may vary depending on top up/down. And stock or aftermarket airbox?

2. How is the drone with and without the factory resonated section 2 x-pipe?

3. To the extent drone occurs, at what rev range does it occur? If it occurs regardless of x-pipe choice, does the x-pipe shift when the drone occurs?

4. Did the x-pipe affect hp/tq? If you have dyno to back up, while leak numbers may be same, how about the delta in low to mid range?

5. Any sound or video clips from interior/exterior?

1. Mine is a coupe
2. Drone was awful, to the point I put the OE mufflers on the next week
3. From 1800 to 2500
4. No idea, never drove it with the stock pipe
5. No videos

My setup was what you described except for the airbox

Karbonious
Euro headers
DFK 100
RE Xpipe
Stromung

Since then I changed to a SS x-pipe and there was no difference at all in sound or drive.

[3002 tii]

Found another clip, almost exactly what I'm looking for... Euro headers + DKF 300hfc + Rogue X + SS Powerloops. Figure this has to be a forum member here...

[Reborn_]

That’s me. I’ll reply in greater detail tomorrow.

https://www.zpost.com/forums/showthread.php?t=1364024

[3002 tii]

Originally Posted by Reborn_

That’s me. I’ll reply in greater detail tomorrow.

https://www.zpost.com/forums/showthread.php?t=1364024

Looking forward to it! I put in 100 cell DKF cats as well your setup is nearly identical to what I am ultimately considering.

[Reborn_]

1. Coupe. AFE airbox. I also have a tune but I doubt that would play much of a role.

2. Section 2 x-pipe did not change drone at all for me.

3. Maupineda hit the nail on the head. Powerloops with my setup droned 1800-2500. X-pipe did not change drone point or affect it in any way.

4. No affect on power that I could feel. No dynos.

5. Previous post.


I'll give you a better explanation of my experience. I started with Euro Header, DKF S1 w/300 cell cats, stock x-pipe, and powerloops. I then swapped the x-pipe for Rogue Engineering. All that did was make the exhaust louder. No change in drone characteristics, no change in power (that I could feel). Next, I switched to SS race cans. That seemed to increase power, but I wouldn't go that far to make that statement. I would characterize it as the car felt less 'restricted' as it climbed in rpm. It of course got a hell of a lot louder, and I went to drone city. I now drone pretty much at any rpm. Powerloops had a better tone than the race cans. Much deeper.

Commentary: with 100 cell cats, you may drone differently and worse than my setup, even with the powerloops. Ultimately, drone is not something I really mind (though my wife rarely rides in the car since I got the race cans).

[3002 tii]

Originally Posted by Reborn_

1. Coupe. AFE airbox.

2. Section 2 x-pipe did not change drone at all for me.

3. Maupineda hit the nail on the head. Powerloops with my setup droned 1800-2500. X-pipe did not change drone point or affect it in any way.

4. No affect on power that I could feel. No dynos.

5. Previous post.


I'll give you a better explanation of my experience. I started with Euro Header, DKF S1 w/300 cell cats, stock x-pipe, and powerloops. I then swapped the x-pipe for Rogue Engineering. All that did was make the exhaust louder. No change in drone characteristics, no change in power (that I could feel). Next, I switched to SS race cans. That seemed to increase power, but I wouldn't go that far to make that statement. I would characterize it as the car felt less 'restricted' as it climbed in rpm. It of course got a hell of a lot louder, and I went to drone city. I now drone pretty much at any rpm. Powerloops had a better tone than the race cans. Much deeper.

Commentary: with 100 cell cats, you may drone differently and worse than my setup, even with the powerloops. Ultimately, drone is not something I really mind (though my wife rarely rides in the car since I got the race cans).

So Powerloops with stock x-pipe => slight drone 1800 to 2500
Powerloops with Rogue x-pipe => louder overall, no change in drone
Switching to Race cans (while keeping RE x-pipe) => drone city

Interesting... I really wonder if coupe vs roadster makes that much of a difference then. OG member Starscream ran Euro headers + modified US section 1 + SS x-pipe and Powerloops and swore no drone whatsoever. I think in the roadster, the cabin is not exposed to the open trunk like you are in the hatch. And with top folded down, that probably does an even better job suppressing the noise.

This was all very helpful btw. Maybe the answer is factory x-pipe and experiment between 100 and 300 cell DKFs. Though I don't recall dropping down to 100 making a big difference.

[Reborn_]

Originally Posted by 3002 tii

So Powerloops with stock x-pipe => slight drone 1800 to 2500
Powerloops with Rogue x-pipe => louder overall, no change in drone
Switching to Race cans (while keeping RE x-pipe) => drone city

Interesting... I really wonder if coupe vs roadster makes that much of a difference then. OG member Starscream ran Euro headers + modified US section 1 + SS x-pipe and Powerloops and swore no drone whatsoever. I think in the roadster, the cabin is not exposed to the open trunk like you are in the hatch. And with top folded down, that probably does an even better job suppressing the noise.

This was all very helpful btw. Maybe the answer is factory x-pipe and experiment between 100 and 300 cell DKFs. Though I don't recall dropping down to 100 making a big difference.

Yup, you're interpreting correctly.

I'm assuming starscream had a roadster? I definitely think a roadster would behave differently. I swear I can feel the reverberations in the hatch. having no roof would help the sound escape instead of bounce around, and even with the top up, cloth absorbs sound better than metal. So I am convinced things will play out differently in a roadster, the big question is, by how much?

Relative to starscream's experience, I do think US/Euro S1 will tone things down substantially. My next move is to swap S1 to Euro (I have it, but may not install for another 9 months). I can comment back when I do, but I'm sure you're looking to make some changes sooner than that.

[3002 tii]

Originally Posted by Reborn_

Yup, you're interpreting correctly.

I'm assuming starscream had a roadster? I definitely think a roadster would behave differently. I swear I can feel the reverberations in the hatch. having no roof would help the sound escape instead of bounce around, and even with the top up, cloth absorbs sound better than metal. So I am convinced things will play out differently in a roadster, the big question is, by how much?

Relative to starscream's experience, I do think US/Euro S1 will tone things down substantially. My next move is to swap S1 to Euro (I have it, but may not install for another 9 months). I can comment back when I do, but I'm sure you're looking to make some changes sooner than that.

I am looking to make a decision sooner but holding off (and not burning money) isn't a bad thing neither. Just at the point where trying to knock out the remaining winter mods so I can enjoy my car fully as soon as warm weather rolls around.

US section 1 vs Euro vs DKF 100/300 - seems like splitting hairs, and you'd hope it doesn't come down to that marginal difference determining whether you have drone or not.

Starscream had a roadster and I really think that's the difference, ironic if you think about it...

Another thing to throw in the mix is to add one of those exhaust cone inserts, similar to the RPi silencer. Theoretically it'd reduce flow but when it so far down stream (essentially right before exit) I can't see it robbing that much hp. And between that or upping the cats back to 300 cell, I'd rather stick with 100's and add an insert at the end of the system.

I'll report back my findings as well. Who knows maybe between us 3 and Filter we get this mystery solved once and for all =)

[Reborn_]

Yea, I'll be reporting back in either case to build the info base for everyone. I agree that US/Euro S1 should be about the same, but the reason I think either of those will be substantially different (i.e. quieter and less drone) than the DKF, even with 300 cell cat, is the size and density of the OE cats is substantially more restrictive. I'm only making that change because of CA smog reasons - if it does quiet things down, I'll likely switch to RPI cans as a next step.

Do you have a roadster?

[3002 tii]

Originally Posted by Reborn_

Yea, I'll be reporting back in either case to build the info base for everyone. I agree that US/Euro S1 should be about the same, but the reason I think either of those will be substantially different (i.e. quieter and less drone) than the DKF, even with 300 cell cat, is the size and density of the OE cats is substantially more restrictive. I'm only making that change because of CA smog reasons - if it does quiet things down, I'll likely switch to RPI cans as a next step.

Do you have a roadster?

Sorry should've specified, yes I have a roadster.

I thought OE section 1 would be similar to DKF 300 with only difference being the overall length of the cat. Plus considering the drone was only present after you guys went with Powerloops tells me the changing up the cat upstream isn't going to be very impactful. Rather the hardware change needs to come down to where the muffler is (or where muffler meets x-pipe)...

[pokeybritches]

Originally Posted by 3002 tii

Sorry should've specified, yes I have a roadster.

I thought OE section 1 would be similar to DKF 300 with only difference being the overall length of the cat. Plus considering the drone was only present after you guys went with Powerloops tells me the changing up the cat upstream isn't going to be very impactful. Rather the hardware change needs to come down to where the muffler is (or where muffler meets x-pipe)...

I think the s-pipe has a bigger impact once you move to catless headers. The stock s-pipe is 400 cell IIRC, although it's not completely filled with "cat material". Here's a pic of the stock U.S. s-pipe and DKF side-by-side.

[mziggy16]

I’m basically in the same boat. This thread is helpful.

I was planning on Euro header and DKF S1 w/300 cell and then stock the rest of the way at first, and then swapping the cans later on if needed.

3002 - Do you already have the DKF setup? I haven’t seen any w/300 cells recently.

Also, are you guys just going to deal with a CEL or hope that the DKF setup will avoid the code? Or tune?

I was hoping to avoid a CEL with the 300 cell DKF setup, but from what I’ve read, it looks like a toss up.

-Mike

[3002 tii]

Originally Posted by mziggy16

I’m basically in the same boat. This thread is helpful.

I was planning on Euro header and DKF S1 w/300 cell and then stock the rest of the way at first, and then swapping the cans later on if needed.

3002 - Do you already have the DKF setup? I haven’t seen any w/300 cells recently.

Also, are you guys just going to deal with a CEL or hope that the DKF setup will avoid the code? Or tune?

I was hoping to avoid a CEL with the 300 cell DKF setup, but from what I’ve read, it looks like a toss up.

-Mike

Yes I have the DKF section 1, both the 100 and 300 cell cats. Originally ran 300 as-is, no codes. Then I switched to 100's to get that extra performance. I used an o2 spacer just in case and luckily got no codes. Not sure if I could've gotten away w/o the spacers but for $25 figured may as well throw them in and be done with it.

Right now with Euro headers, DKF 100 and stock x pipe and cans, exhaust is sportier but still very tame. Hence why I'm considering going with aftermarket cans. RPI, Diablo, and SS Race are off the table b/c I know those are the loudest. From what I gathered here, Stromungs will likely drone with this setup so it's come down to Powerloops...

[JimBob0047]

My setup. AFE Intake, US catted headers, DKF resonated section 1, stock x pipe and Stromung mufflers. No drone and no rasp. I've also been wondering how the addition of a carbon air box and euro headers would change my sound and wether or not to swap in the 100/300 cell cats and add a Rouge x pipe once the air box and headers are installed.

[mziggy16]

Originally Posted by 3002 tii

Yes I have the DKF section 1, both the 100 and 300 cell cats. Originally ran 300 as-is, no codes. Then I switched to 100's to get that extra performance. I used an o2 spacer just in case and luckily got no codes. Not sure if I could've gotten away w/o the spacers but for $25 figured may as well throw them in and be done with it.

Right now with Euro headers, DKF 100 and stock x pipe and cans, exhaust is sportier but still very tame. Hence why I'm considering going with aftermarket cans. RPI, Diablo, and SS Race are off the table b/c I know those are the loudest. From what I gathered here, Stromungs will likely drone with this setup so it's come down to Powerloops...

Tell me more about these o2 spacers. Where'd you get them?

[3002 tii]

Originally Posted by JimBob0047

My setup. AFE Intake, US catted headers, DKF resonated section 1, stock x pipe and Stromung mufflers. No drone and no rasp. I've also been wondering how the addition of a carbon air box and euro headers would change my sound and wether or not to swap in the 100/300 cell cats and add a Rouge x pipe once the air box and headers are installed.

No drone for another roadster owner...

though catted headers makes a big difference.

Originally Posted by mziggy16

Tell me more about these o2 spacers. Where'd you get them?

https://www.zpost.com/forums/showthread.php?t=1673908

They’re all over eBay and Amazon, etc.

[JimBob0047]

Originally Posted by 3002 tii

No drone for another roadster owner...

I will say that when I was running the stock section 1 and DKF resonated section 1 with the AFE exhaust/x pipe there was a lot of drone.

[Syed///M]

Originally Posted by 3002 tii

https://www.zpost.com/forums/showthread.php?t=1673908

They’re all over eBay and Amazon, etc.

I'm running SS section 1, RE x-pipe and RPI mufflers. there is definitely drone at highway speeds. But I don't have a CEL yet, not sure if I was supposed to? also considering euro headers instead of my current US catted headers and wondering how that will change my setup? I will run a tune though with euro headers.

[3002 tii]

Originally Posted by Syed///M

I'm running SS section 1, RE x-pipe and RPI mufflers. there is definitely drone at highway speeds. But I don't have a CEL yet, not sure if I was supposed to? also considering euro headers instead of my current US catted headers and wondering how that will change my setup? I will run a tune though with euro headers.

You’d only get a CEL with catless headers. There’s no o2 sensors behind the section 1 secondary cats so deleting those would have no impact on your readings.

[3002 tii]

Funny how things turn out but I ended up buying those new Powerloops from my shop. I kept resisting but the price was too good and my tax refund is higher than I expected

Anyways, I've owned these cans before but never in conjunction with my current setup which consists of Euro headers + DFK 100 + factory X (section 2). So what's the final verdict regarding drone? My honest feedback:

• Initial Startup: Loud and present but quickly settles down after 20 seconds, remains aggressive but not obnoxious. Has a guttural lurking sound to it.
  
  
• 1800-2000: YES drone but it's limited to this band only. And honestly, I don't spend more than a second here else I'm just lugging the car around in too high of a gear. I probably spend more time in this range when I'm coming to a stop.
  
  
• 2000-2500: Increased bass but no cabin vibration or drone whatsoever. I can see how others could describe this area as being "boomy" but there's a noticeable difference in the positive from below to above 2000. And for me, this "boominess" was only heard from 2000-2200 or so.
  
  
• 2500-5500: Just PERFECT, that exotic Italian tone you wanted and paid for. Everything sounds absolutely balanced from the engine, cabin to exhaust.
  
  
• 5500+: Same as above but to a lesser extent. While the volume drops off a little, here's the kicker. I swear the car pulls harder...

I fully admit any perceived gains in performance is subjective but I plan to put the car back on the dyno. I was just there a month ago after some tuning but will need to go back once more around April.

But if you think I'm crazy, check out these dyno sheets from Supersprint. Yes, it's not 3rd party independent but then again how many exhaust manufacturers do you know that upload dynos for most of their products? With Powerloops and all else same, their Z4 M picked up +6hp/9ft-lb - not bad for just replacing the oe mufflers which seemed pretty efficient to begin with.

Stock M coupe


Comparison: Stock vs. Powerloops


Cold start video