2008 Z4 3.0i Muffler Delete

Manners226 · 02-19-2010, 06:27 PM

Yes I did. But it too isn't that great...As far as the 'ol butt dyno, yeah it helped some. Nothing crazy, it breathes easier up top and is a little snappier reving it. I would say it pulls a little harder, but who knows? It's probably just in my head because it sounds faster...

It grumbles when you let off the throttle at certain rpms and it is a little racey/nasty above 4 grand, but I like it, the overall volume doesn't reall go up just the tone. These cars make peak TQ right before 3 grand and thats when its the loudest, maybe slightly 'boomy'. It doesn't really drone or have any bad resonance though. I think overall it sounds more 'exotic' than 'ricey' if that makes any sense.

Between removing the secondary charcoal air filter and that stupid plastic half-scoop behind the grill that blocks the intake path and now doing the exhaust, it revs much free-er and you get both intake and exhaust sound when the windows or top are down.

Now here is how I really feel...You would have to 'give' me a really high quality full cat-back exhaust that sounded awesome before I would want to change it from how it is now. I'm pretty content.

Incompatible · 02-23-2010, 04:18 PM

Quote:

Originally Posted by Manners226

Yes I did. But it too isn't that great...As far as the 'ol butt dyno, yeah it helped some. Nothing crazy, it breathes easier up top and is a little snappier reving it. I would say it pulls a little harder, but who knows? It's probably just in my head because it sounds faster.

Any plans to throw it on the dyno?

krnnerdboy · 02-23-2010, 07:11 PM

wow that sounds really good

mine is way louder and not bearable as a daily driver but yours sounds like it has a quality exhaust on it. pointer for the tips...after playing w/ mine quite a bit it turns out looking the best when it's at least an 1" out from the bumper b/c our bumpers have a C profile from the side

Manners226 · 02-25-2010, 03:21 PM

Quote:

Originally Posted by Incompatible

Any plans to throw it on the dyno?

Yeah, actually. The local sports car club is trying to get a dyno day together this spring, i'd like to go. Unfortunately, I won't have before and afters, but I would still like to see what it makes.

BTW your Z4M looks fantastic man. Beautiful.

Incompatible · 02-25-2010, 06:42 PM

Quote:

Originally Posted by Manners226

Yeah, actually. The local sports car club is trying to get a dyno day together this spring, i'd like to go. Unfortunately, I won't have before and afters, but I would still like to see what it makes.

BTW your Z4M looks fantastic man. Beautiful.

Oh I wish I had a Z4M..... I'm sure krnnerdboy will appreciated the comment anyway.

Chris04Z4 · 05-06-2010, 03:55 PM

updates?? get the dyno done?

Chris04Z4 · 05-10-2010, 12:25 PM

so i did the muffler delete on saturday.... wow im glad I did. Sounds AMAZING. Not very loud at all... in fact at idle you barely hear it... but give it just a little bit of gas and it growls! Let off the gas and it has a nice gurgle to it. Definatly a must try for any 3.0i..3.0si owners. no real noticable loss of torque... maybe a little but barely.

Incompatible · 05-10-2010, 02:02 PM

Quote:

Originally Posted by Chris04Z4

so i did the muffler delete on saturday.... wow im glad I did. Sounds AMAZING. Not very loud at all... in fact at idle you barely hear it... but give it just a little bit of gas and it growls! Let off the gas and it has a nice gurgle to it. Definatly a must try for any 3.0i..3.0si owners. no real noticable loss of torque... maybe a little but barely.

Any drone?

Chris04Z4 · 05-10-2010, 03:43 PM

a little but thats just because i have the pipes dumped and not out the back right now... just temporary. I basicly cut the muffler off about 6-8in behind the muffler and got that flex tubing from the parts store and just turned it down a little.... the drone is coming from the metal shield that coats the underbody of the car where the muffler was... The sound gets a little trapped in there.

I can promise that the sound is almost perfect. it sounds a lot like a subi or SRT neon... just not as loud. All i can say is do it.... you will not be disapointed.

Incompatible · 05-10-2010, 04:10 PM

[QUOTE=Chris04Z4;7292482].... the drone is coming from the metal shield that coats the underbody of the car where the muffler was... The sound gets a little trapped in there. QUOTE]
Drone is more of a problem with the coupes due to the large "echo chamber" that we have, that's why I asked. When you finish the mod, let us know your thoughts. Thanks

nlink720 · 10-30-2010, 10:35 PM

Guys,

In reliance on the positive results posted here for the muffler delete, I did one. I really wanted to lose weight, and figured that a muffler delete would be better than an aftermarket exhaust. I also figured that the OEM muffler would weigh more than the 21# that it did. Either way, my car is 21# lighter (I want to get my car to under 2,800 lbs).

The sound is just fine from outside the car in that it is not too loud, but sounds great. I have before and after videos.

My problem is that I have unacceptable drone between 1,500 and 3,500 rpm. I need to eliminate this. I wonder why my results would vary from the results posted above.

Everything is stock engine/intake/exhaust-wise except for the rear muffler delete.

I can feel some minor vibration under my feet when driving that was not there before, but it is not like anything is loose, but simply the type of resonant vibration that causes drone.

My questions are as follows:

What can I do to eliminate this drone -- considering that others reportedly don't have it? Why would my car be different?

Can I modify the resonator, perhaps like a Magnaflow, to adjust the drone?
Can I adjust the exhaust pipes slightly?

Any assistance or ideas are greatly appreciated.

2004 BMW Z4 3.0i

3002 tii · 10-30-2010, 11:19 PM

How far did you cut back? What sized piping did you replace with?

nlink720 · 10-30-2010, 11:53 PM

They cut the pipe flush with the OEM muffler inlet and used slightly larger piping. Perhaps 1/4" larger, or about 2-1/4? What are your thoughts?

SteveInfante · 10-30-2010, 11:57 PM

This will be my first MOD.

nlink720 · 10-31-2010, 12:11 AM

I have a quickly made compilation of videos that I will post here shortly.

Incompatible · 10-31-2010, 12:27 AM

I'm taking a guess here, but I think what you did with the larger diameter pipes was to add megaphones to the exhaust. Keeping in mind that you now have no restriction (muffler) in the section you removed, you could go to a "small" diameter single pipe about 2 1/4" instead of what you have with a 'Y" to dual tips. The flow restriction would be minimal compared to that of the muffler you removed and I think the majority of the resonance would vanish. Larger diameter tubes are not always the best way to go.

An option which I have been considering is a dynomax super turbo muffler in a 2 1/4 or 2 1/2 inch inlet/outlet size. This option came from an interesting article on mufflers and exhaust flow. http://www.superchevy.com/technical/...xh/index1.html Down towards the bottom on the left is a series of images (mufflers) and short commentaries which are somewhat informative.

To be up front, I have not personally heard either of the above options, these come from others who I believe have more understanding and experience then I do. As you can tell from my earlier posts, I am aware of and concerned about drone and I still haven't heard/found that just right sound.

nlink720 · 10-31-2010, 12:33 AM

Incompatible, that is not unreasonable. That is somewhat along the lines of what I did the other day when I purchased some 2-1/4" diameter by 3" long pipes from Autozone and bent the rear parts nearly closed to see what would happen. The drone went away, but the exhaust was very restricted. I guess I could build in an adjustable valve, but I would first prefer to have something that doesn't need to be adjusted. Also, we are skipping the fact that the 2008 has a slightly different engine. I have the M54.

Here is a video anyway: http://www.youtube.com/watch?v=7vkGzAPK2qo

Also, Dubbedown, here was this summer in NJ...http://www.youtube.com/watch?v=O9PI_kWmjX8

nlink720 · 10-31-2010, 08:56 AM

----

I just realized that a muffler delete, even one that meets sound requirements, is not permitted in STR class. So all this experimentation has been a waste for me.

Hope someone else benefits. I hope the shop can reattach my oem muffler. I think bastuck would be about the only exhaust I would do, but I was primarily after weight savings and not sound, so now that I know my oem muffler weighs 21 lbs I will just reinstall it rather than paying way up for an exhaust that will not drone.

Let me know if I can help anyone who does plan a muffler delete though

02-19-2010, 06:27 PM	#23
Manners226 Racing Enthusiast 4 Rep 27 Posts Drives: 2008 Z4 3.0i Blk/Blk 6MT Sport Join Date: Jul 2009 Location: Knoxville, TN iTrader: (0)	Yes I did. But it too isn't that great...As far as the 'ol butt dyno, yeah it helped some. Nothing crazy, it breathes easier up top and is a little snappier reving it. I would say it pulls a little harder, but who knows? It's probably just in my head because it sounds faster... It grumbles when you let off the throttle at certain rpms and it is a little racey/nasty above 4 grand, but I like it, the overall volume doesn't reall go up just the tone. These cars make peak TQ right before 3 grand and thats when its the loudest, maybe slightly 'boomy'. It doesn't really drone or have any bad resonance though. I think overall it sounds more 'exotic' than 'ricey' if that makes any sense. Between removing the secondary charcoal air filter and that stupid plastic half-scoop behind the grill that blocks the intake path and now doing the exhaust, it revs much free-er and you get both intake and exhaust sound when the windows or top are down. Now here is how I really feel...You would have to 'give' me a really high quality full cat-back exhaust that sounded awesome before I would want to change it from how it is now. I'm pretty content. __________________ 2008 Z4 3.0i 6MT W/ Sport Pkg
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02-23-2010, 07:11 PM	#25
krnnerdboy Colonel 190 Rep 2,431 Posts Drives: v10 m6 Join Date: Nov 2008 Location: so cal iTrader: (10)	wow that sounds really good mine is way louder and not bearable as a daily driver but yours sounds like it has a quality exhaust on it. pointer for the tips...after playing w/ mine quite a bit it turns out looking the best when it's at least an 1" out from the bumper b/c our bumpers have a C profile from the side __________________ F80 m3, 997 gt3, 14 ram ctd, f15 x5, drz400sm Gone:z4m, boss 302, c6 z06, m6,z3m
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05-06-2010, 03:55 PM	#28
Chris04Z4 Private First Class 14 Rep 100 Posts Drives: 2004 Z4 Roadster 3.0i Join Date: Oct 2008 Location: Atlanta GA iTrader: (0)	updates?? get the dyno done? __________________
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05-10-2010, 12:25 PM	#29
Chris04Z4 Private First Class 14 Rep 100 Posts Drives: 2004 Z4 Roadster 3.0i Join Date: Oct 2008 Location: Atlanta GA iTrader: (0)	so i did the muffler delete on saturday.... wow im glad I did. Sounds AMAZING. Not very loud at all... in fact at idle you barely hear it... but give it just a little bit of gas and it growls! Let off the gas and it has a nice gurgle to it. Definatly a must try for any 3.0i..3.0si owners. no real noticable loss of torque... maybe a little but barely. __________________
	Appreciate 0 Quote

05-10-2010, 03:43 PM	#31
Chris04Z4 Private First Class 14 Rep 100 Posts Drives: 2004 Z4 Roadster 3.0i Join Date: Oct 2008 Location: Atlanta GA iTrader: (0)	a little but thats just because i have the pipes dumped and not out the back right now... just temporary. I basicly cut the muffler off about 6-8in behind the muffler and got that flex tubing from the parts store and just turned it down a little.... the drone is coming from the metal shield that coats the underbody of the car where the muffler was... The sound gets a little trapped in there. I can promise that the sound is almost perfect. it sounds a lot like a subi or SRT neon... just not as loud. All i can say is do it.... you will not be disapointed. __________________
	Appreciate 0 Quote

05-10-2010, 04:10 PM	#32
Incompatible Major 55 Rep 1,224 Posts Drives: 07 AW Z4C 3.0Si Join Date: Aug 2007 Location: San Diego iTrader: (1)	[QUOTE=Chris04Z4;7292482].... the drone is coming from the metal shield that coats the underbody of the car where the muffler was... The sound gets a little trapped in there. QUOTE] Drone is more of a problem with the coupes due to the large "echo chamber" that we have, that's why I asked. When you finish the mod, let us know your thoughts. Thanks __________________ If you can't take the time to teach a kid something good, someone will take the time to teach them something bad.
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10-30-2010, 10:35 PM	#33
nlink720 Second Lieutenant 19 Rep 231 Posts Drives: 2004 BMW Z4 Roadster Join Date: Jan 2008 Location: Maryland iTrader: (3)	HELP with Muffler Delete Drone!! Guys, In reliance on the positive results posted here for the muffler delete, I did one. I really wanted to lose weight, and figured that a muffler delete would be better than an aftermarket exhaust. I also figured that the OEM muffler would weigh more than the 21# that it did. Either way, my car is 21# lighter (I want to get my car to under 2,800 lbs). The sound is just fine from outside the car in that it is not too loud, but sounds great. I have before and after videos. My problem is that I have unacceptable drone between 1,500 and 3,500 rpm. I need to eliminate this. I wonder why my results would vary from the results posted above. Everything is stock engine/intake/exhaust-wise except for the rear muffler delete. I can feel some minor vibration under my feet when driving that was not there before, but it is not like anything is loose, but simply the type of resonant vibration that causes drone. My questions are as follows: What can I do to eliminate this drone -- considering that others reportedly don't have it? Why would my car be different? Can I modify the resonator, perhaps like a Magnaflow, to adjust the drone? Can I adjust the exhaust pipes slightly? Any assistance or ideas are greatly appreciated. 2004 BMW Z4 3.0i __________________ FS: Leather Recaro Pole Position Seats & Hardware
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10-30-2010, 11:19 PM	#34
3002 tii Lieutenant General 2280 Rep 12,565 Posts Drives: Z4 M, X5, GX460 Join Date: Apr 2008 Location: CT iTrader: (99) Garage List F15 X5 xDrive35i [8.75] E86 Z4 M [10.00] F10 550i (Retired) [9.17] F25 X3 xDrive35i (R ... [9.43] E82 135is (Retired) [9.50] E85 Z4 M (Retired) [9.41] E90 328i xDrive (Re ... [9.25] E86 Z4 3.0si (Retired) [9.20]	How far did you cut back? What sized piping did you replace with? __________________ Follow for latest mods
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10-30-2010, 11:53 PM	#35
nlink720 Second Lieutenant 19 Rep 231 Posts Drives: 2004 BMW Z4 Roadster Join Date: Jan 2008 Location: Maryland iTrader: (3)	They cut the pipe flush with the OEM muffler inlet and used slightly larger piping. Perhaps 1/4" larger, or about 2-1/4? What are your thoughts? __________________ FS: Leather Recaro Pole Position Seats & Hardware
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10-30-2010, 11:57 PM	#36
SteveInfante NewFinishColumbia/detailer 604 Rep 2,096 Posts Drives: 2015 F31 xDrive Join Date: Sep 2010 Location: Columbia, SC iTrader: (0)	This will be my first MOD. __________________ 328 F31 xDrive/OSM/Venetian Luxury Line/Cold Weather/Premium/Driving Assist/Nav/Tech "Golden Goose" 78' Honda CB400A project http://www.instagram.com/steve_inf31
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10-31-2010, 12:11 AM	#37
nlink720 Second Lieutenant 19 Rep 231 Posts Drives: 2004 BMW Z4 Roadster Join Date: Jan 2008 Location: Maryland iTrader: (3)	I have a quickly made compilation of videos that I will post here shortly. __________________ FS: Leather Recaro Pole Position Seats & Hardware
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10-31-2010, 12:27 AM	#38
Incompatible Major 55 Rep 1,224 Posts Drives: 07 AW Z4C 3.0Si Join Date: Aug 2007 Location: San Diego iTrader: (1)	I'm taking a guess here, but I think what you did with the larger diameter pipes was to add megaphones to the exhaust. Keeping in mind that you now have no restriction (muffler) in the section you removed, you could go to a "small" diameter single pipe about 2 1/4" instead of what you have with a 'Y" to dual tips. The flow restriction would be minimal compared to that of the muffler you removed and I think the majority of the resonance would vanish. Larger diameter tubes are not always the best way to go. An option which I have been considering is a dynomax super turbo muffler in a 2 1/4 or 2 1/2 inch inlet/outlet size. This option came from an interesting article on mufflers and exhaust flow. http://www.superchevy.com/technical/...xh/index1.html Down towards the bottom on the left is a series of images (mufflers) and short commentaries which are somewhat informative. To be up front, I have not personally heard either of the above options, these come from others who I believe have more understanding and experience then I do. As you can tell from my earlier posts, I am aware of and concerned about drone and I still haven't heard/found that just right sound. __________________ If you can't take the time to teach a kid something good, someone will take the time to teach them something bad.
	Appreciate 0 Quote

10-31-2010, 12:33 AM	#39
nlink720 Second Lieutenant 19 Rep 231 Posts Drives: 2004 BMW Z4 Roadster Join Date: Jan 2008 Location: Maryland iTrader: (3)	Incompatible, that is not unreasonable. That is somewhat along the lines of what I did the other day when I purchased some 2-1/4" diameter by 3" long pipes from Autozone and bent the rear parts nearly closed to see what would happen. The drone went away, but the exhaust was very restricted. I guess I could build in an adjustable valve, but I would first prefer to have something that doesn't need to be adjusted. Also, we are skipping the fact that the 2008 has a slightly different engine. I have the M54. Here is a video anyway: http://www.youtube.com/watch?v=7vkGzAPK2qo Also, Dubbedown, here was this summer in NJ...http://www.youtube.com/watch?v=O9PI_kWmjX8 __________________ FS: Leather Recaro Pole Position Seats & Hardware Last edited by nlink720; 10-31-2010 at 12:38 AM..
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10-31-2010, 08:56 AM	#40
nlink720 Second Lieutenant 19 Rep 231 Posts Drives: 2004 BMW Z4 Roadster Join Date: Jan 2008 Location: Maryland iTrader: (3)	---- I just realized that a muffler delete, even one that meets sound requirements, is not permitted in STR class. So all this experimentation has been a waste for me. Hope someone else benefits. I hope the shop can reattach my oem muffler. I think bastuck would be about the only exhaust I would do, but I was primarily after weight savings and not sound, so now that I know my oem muffler weighs 21 lbs I will just reinstall it rather than paying way up for an exhaust that will not drone. Let me know if I can help anyone who does plan a muffler delete though __________________ FS: Leather Recaro Pole Position Seats & Hardware
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