Vibration around car after AR DP install

M-POWERED- · 02-04-2011, 07:24 AM

Just installed catless AR DPs on my xi. I noticed that at around 1k rpm there is a vibration around the car caused by DPs. Is it normal? Please comment.

Mike@N54Tuning.com · 02-04-2011, 07:43 AM

Quote:

Originally Posted by m-power-

Just installed catless AR DPs on my xi. I noticed that at around 1k rpm there is a vibration around the car caused by DPs. Is it normal? Please comment.

Probably miss aligned install. The fitment on the XI is extra tight, and one of my customers had this issue last year. Went back to the shop and they rotated one of the pipes slightly and the vibration was gone.

The fitment with these is spot on so there shouldn't be any vibration.

Mike

enrita · 02-04-2011, 07:44 AM

what kind of vibrations? like they are touching each other? You need to inspect them and see they clear each other and arent touching.

M-POWERED- · 02-04-2011, 08:03 AM

I took part in installation process. First we tightened DPs to midpipes and then DPs to turbos. They have 1.5-2mm clearance between each other. Vibration caused by exhaust, while increasing revvs. Don't think they touch each other beacause in this case i would have heard metallic sound. Thinking now of wrapping them with termal cloth)

Mike@N54Tuning.com · 02-04-2011, 09:16 AM

Maybe its not the DPs but the exhaust is rattling somehow. If you have clearance with the pipes then its not them as there is nothing that can rattle. Check the exhaust heat shields and hangers to ensure nothing shifted/broke during the install.

Mike

cn555ic · 02-04-2011, 09:46 AM

Quote:

Originally Posted by m-power-

I took part in installation process. First we tightened DPs to midpipes and then DPs to turbos. They have 1.5-2mm clearance between each other. Vibration caused by exhaust, while increasing revvs. Don't think they touch each other beacause in this case i would have heard metallic sound. Thinking now of wrapping them with termal cloth)

Heatshield of the DPs can be also a culprit in rattling

enrita · 02-04-2011, 09:51 AM

or maybe is just droning like crazy. Are you catless? AT ?

Pseudo Nim · 02-04-2011, 09:53 AM

xi + AT is a recipe for rattling. I don't know, but I would say it's close to impossible to NOT touch SOME part of the body with the install - plus consider that when hot, the exhaust extends by almost 1", so that plays a part in the noise too (ie rattle when cold, no rattle when hot, or reverse).

I was on the lift like three times to try to solve mine, and it's still SOMEWHAT present

stratplaya06 · 02-04-2011, 09:58 AM

I have an xi AT and have a bit more vibration than with just my bmw perf. mufflers, but I really don't think the dp's are touching anything. Before the bmw perf. mufflers, I had a shotty exhaust shop make me a custom exhaust and they didn't use rubber isolaters (such morons...), so I know well what vibration from the pipes touching the car feels like, and this really doesn't seem rear compartment-rattling enuogh. I think a little bit more vibration is normal, but anything past that should be checked out.

Pseudo Nim · 02-04-2011, 10:01 AM

Quote:

Originally Posted by stratplaya06

I have an xi AT and have a bit more vibration than with just my bmw perf. mufflers, but I really don't think the dp's are touching anything. Before the bmw perf. mufflers, I had a shotty exhaust shop make me a custom exhaust and they didn't use rubber isolaters (such morons...), so I know well what vibration from the pipes touching the car feels like, and this really doesn't seem rear compartment-rattling enuogh. I think a little bit more vibration is normal, but anything past that should be checked out.

Do you hear more turbo spoolup/down compared to stock?

cn555ic · 02-04-2011, 10:01 AM

Quote:

Originally Posted by Pseudo Nim

Do you hear more turbo spoolup/down compared to stock?

Thats a given to hear more turbo spool!!

Pseudo Nim · 02-04-2011, 10:03 AM

Quote:

Originally Posted by cn555ic

Thats a given to hear more turbo spool!!

Sorry I guess I should be more precise: do you hear a SMOOTH spoolup/down during acceleration, or does it get interrupted by bumps?

stratplaya06 · 02-04-2011, 10:03 AM

Oh yes, so much more, and it is a nice smooth spool up/down. It sounds unreal. I have a bit of rasp when driving very hard/when the meth kicks in, but at this point it's not worth adding resonators to, as I have people asking me if it is some sort of exotic all the time (lol).

cn555ic · 02-04-2011, 10:06 AM

Quote:

Originally Posted by Pseudo Nim

Sorry I guess I should be more precise: do you hear a SMOOTH spoolup/down during acceleration, or does it get interrupted by bumps?

Spool up is very smooth and when its spooling down its smooth also but its drowned out with the gurgle of the exhaust though!

cn555ic · 02-04-2011, 10:07 AM

Quote:

Originally Posted by stratplaya06

Oh yes, so much more, and it is a nice smooth spool up/down. It sounds unreal. I have a bit of rasp when driving very hard/when the meth kicks in, but at this point it's not worth adding resonators to, as I have people asking me if it is some sort of exotic all the time (lol).

Thats raspy note I couldn't stand and cold startups it was like waking up the dead...The resonators took care of all that!

Bimmer This · 02-04-2011, 10:07 AM

Quote:

Originally Posted by cn555ic

Heatshield of the DPs can be also a culprit in rattling

This! Is the heat shield still installed or is it removed?

Pseudo Nim · 02-04-2011, 10:09 AM

Quote:

Originally Posted by stratplaya06

Oh yes, so much more, and it is a nice smooth spool up/down. It sounds unreal. I have a bit of rasp when driving very hard/when the meth kicks in, but at this point it's not worth adding resonators to, as I have people asking me if it is some sort of exotic all the time (lol).

On mine, the spoolup / down sound is very pronounced, but when cold, there's some funny business sound-wise, esp when hitting bumps. When hot, it's fine. Same for vibration: when driving over rough terrain, there's some rattling. The weird thing is, we went over the whole exhaust line up to the turbos, and we can't find ANYWHERE it could possibly be rubbing... so I don't know wtf.

I almost feel like my DPs touch something, which amplifies the turbo sound through the body - and when they DO NOT touch anything the turbo sound disappears (well, gets reduced significantly).

Mine are VK, though, not AR - but the fitment seemed to be spot on when we installed them.

cn555ic · 02-04-2011, 10:09 AM

Quote:

Originally Posted by Bimmer This

This! Is the heat shield still installed or is it removed?

Heatshield near the DP area is from what I know of all the installs is not removed...I just bent and shaped it to make sure it has clearance from the DPs

Pseudo Nim · 02-04-2011, 10:10 AM

Quote:

Originally Posted by Bimmer This

This! Is the heat shield still installed or is it removed?

Hmmm.. if the heatshield is what I think it is (I was looking for pics, can't find any) then mine is still on. We did verify spacing though (spaced it out a bit with washers to be sure).

[edit] oh wtf this?? http://www.e90post.com/forums/showpo...43&postcount=1 -- no, that was def not removed, and is it even OK to remove it? Seems like it.... well..... shields from the heat.

cn555ic · 02-04-2011, 10:12 AM

Quote:

Originally Posted by Pseudo Nim

On mine, the spoolup / down sound is very pronounced, but when cold, there's some funny business sound-wise, esp when hitting bumps. When hot, it's fine. Same for vibration: when driving over rough terrain, there's some rattling. The weird thing is, we went over the whole exhaust line up to the turbos, and we can't find ANYWHERE it could possibly be rubbing... so I don't know wtf.

I almost feel like my DPs touch something, which amplifies the turbo sound through the body - and when they DO NOT touch anything the turbo sound disappears (well, gets reduced significantly).

Mine are VK, though, not AR - but the fitment seemed to be spot on when we installed them.

I am not sure about VKs fitment but very familiar with ARs...Even though they are different makes the usual suspects of noise are the heatshields, DPs not adjusted correctly but in your case they are 2.5 inch which should have alot of clearance compared to AR 3 inch where there is almost no clearance and to fit them on they must be PERFECT...

stratplaya06 · 02-04-2011, 10:13 AM

Quote:

Originally Posted by cn555ic

Thats raspy note I couldn't stand and cold startups it was like waking up the dead...The resonators took care of all that!

You have catless midpipes, though, right?

I still have the cats in mine, as I wanted slightly less sound, and no smell. I think I would definitely need resonators if I was to get rid of the secondary cats.

As far as VK fitment goes, I know they are usually known for good fitment, but with the xi DP install costing me 450 bucks, I did not want to take any fitment chances. Found a second hand (never used) set of AR's, and had them ceramic coated, and my installer and I have nothing but great things to say.

cn555ic · 02-04-2011, 10:13 AM

Quote:

Originally Posted by Pseudo Nim

Hmmm.. if the heatshield is what I think it is (I was looking for pics, can't find any) then mine is still on. We did verify spacing though (spaced it out a bit with washers to be sure).

[edit] oh wtf this?? http://www.e90post.com/forums/showpo...43&postcount=1 -- no, that was def not removed, and is it even OK to remove it? Seems like it.... well..... shields from the heat.

Spaced it out with washers??

02-04-2011, 07:24 AM	#1
M-POWERED- Private 12 Rep 70 Posts Drives: Porsche Join Date: Jul 2010 Location: Earth iTrader: (0)	Vibration around car after AR DP install Just installed catless AR DPs on my xi. I noticed that at around 1k rpm there is a vibration around the car caused by DPs. Is it normal? Please comment.
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02-04-2011, 07:44 AM	#3
enrita Major General 161 Rep 7,377 Posts Drives: 335i - Big turbos Join Date: Sep 2008 Location: Italian in Sweden iTrader: (0)	what kind of vibrations? like they are touching each other? You need to inspect them and see they clear each other and arent touching. __________________ 07 335i AT - MOTIV 750 - MHD E85 BMS flash - BMS PI - JB4G5 - Okada Coils - NGK 5992 Plugs - Helix IC - Snow Stg. 3 - Stett CP - Custom midpipes with 100 HJS Cats - Bastuck Quad - PSS10 - QUAIFE LSD - BMS OCC - Forge DVs - AR OC - ALCON BBK - M3 Chassi - Dinan CP - Velocity M rear Toe arms - Advan RZ-DF - LUX H8 - Level 10 AT upgrade
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02-04-2011, 08:03 AM	#4
M-POWERED- Private 12 Rep 70 Posts Drives: Porsche Join Date: Jul 2010 Location: Earth iTrader: (0)	I took part in installation process. First we tightened DPs to midpipes and then DPs to turbos. They have 1.5-2mm clearance between each other. Vibration caused by exhaust, while increasing revvs. Don't think they touch each other beacause in this case i would have heard metallic sound. Thinking now of wrapping them with termal cloth)
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02-04-2011, 09:16 AM	#5
Mike@N54Tuning.com Joint Chiefs of Staff 5057 Rep 116,213 Posts Drives: 2007 335i, 2015 M3 Join Date: Dec 2008 Location: N54tuning.com iTrader: (89)	Maybe its not the DPs but the exhaust is rattling somehow. If you have clearance with the pipes then its not them as there is nothing that can rattle. Check the exhaust heat shields and hangers to ensure nothing shifted/broke during the install. Mike
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02-04-2011, 09:51 AM	#7
enrita Major General 161 Rep 7,377 Posts Drives: 335i - Big turbos Join Date: Sep 2008 Location: Italian in Sweden iTrader: (0)	or maybe is just droning like crazy. Are you catless? AT ? __________________ 07 335i AT - MOTIV 750 - MHD E85 BMS flash - BMS PI - JB4G5 - Okada Coils - NGK 5992 Plugs - Helix IC - Snow Stg. 3 - Stett CP - Custom midpipes with 100 HJS Cats - Bastuck Quad - PSS10 - QUAIFE LSD - BMS OCC - Forge DVs - AR OC - ALCON BBK - M3 Chassi - Dinan CP - Velocity M rear Toe arms - Advan RZ-DF - LUX H8 - Level 10 AT upgrade
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02-04-2011, 09:53 AM	#8
Pseudo Nim twinborific 121 Rep 4,836 Posts Drives: fast, sometimes slow Join Date: Nov 2008 Location: i am a citizen of the world iTrader: (9)	xi + AT is a recipe for rattling. I don't know, but I would say it's close to impossible to NOT touch SOME part of the body with the install - plus consider that when hot, the exhaust extends by almost 1", so that plays a part in the noise too (ie rattle when cold, no rattle when hot, or reverse). I was on the lift like three times to try to solve mine, and it's still SOMEWHAT present __________________ Doko ni itemo, hito wa tsunagatte iru...
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02-04-2011, 09:58 AM	#9
stratplaya06 Captain 48 Rep 967 Posts Drives: 2008 E92 335xi-SOLD 5.0 Miata Join Date: May 2008 Location: Maryland iTrader: (10)	I have an xi AT and have a bit more vibration than with just my bmw perf. mufflers, but I really don't think the dp's are touching anything. Before the bmw perf. mufflers, I had a shotty exhaust shop make me a custom exhaust and they didn't use rubber isolaters (such morons...), so I know well what vibration from the pipes touching the car feels like, and this really doesn't seem rear compartment-rattling enuogh. I think a little bit more vibration is normal, but anything past that should be checked out. __________________ \| PROcede Rev3 \| Vishnu Meth \| DCI \| BMW Perf. Exhaust \| AR Coated/Catless \| CP-E FMIC \| Quaife \|
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02-04-2011, 10:03 AM	#13
stratplaya06 Captain 48 Rep 967 Posts Drives: 2008 E92 335xi-SOLD 5.0 Miata Join Date: May 2008 Location: Maryland iTrader: (10)	Oh yes, so much more, and it is a nice smooth spool up/down. It sounds unreal. I have a bit of rasp when driving very hard/when the meth kicks in, but at this point it's not worth adding resonators to, as I have people asking me if it is some sort of exotic all the time (lol). __________________ \| PROcede Rev3 \| Vishnu Meth \| DCI \| BMW Perf. Exhaust \| AR Coated/Catless \| CP-E FMIC \| Quaife \|
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