N55 xDrive Downpipe Install

TheGoodTheBadTheUgly · 03-01-2019, 01:06 PM

As the title says, I am going to install downpipes for my car soon. The only problem is that's it seems to be a process that is way more hectic than on a RWD 335.

So I would like to know, preferably from people who did it on their xDrive 335 or from people who knows about the process, how to install the downpipes.

I have heard that you need to drop the subframe in order to access the downpipes mounting point. Does the whole subframe have to come off or you can just lower it a bit? Do you have to remove the steering rack?

Any details or insight is appreciated!

RoarinForeign · 03-01-2019, 01:59 PM

You will just have to lower the subframe. It's definitely a doable job but it's a pita. There are a few good YouTube videos and forum posts about the process of the install. My main problem was I didn't take the bracket that holds he thing to the transmission off, after I did that the fat cat slid right out.

TheGoodTheBadTheUgly · 03-01-2019, 02:26 PM

Quote:

Originally Posted by RoarinForeign

You will just have to lower the subframe. It's definitely a doable job but it's a pita. There are a few good YouTube videos and forum posts about the process of the install. My main problem was I didn't take the bracket that holds he thing to the transmission off, after I did that the fat cat slid right out.

Ok good to know. I viewed a video of a N54 subframe lowering I believe, so I do have a slight of an idea of how to do it.

I was searching the forums a bit and on a old downpipe install post some people where saying that they did their xDrivee N55 without even touching the subframe.

Is that even possible?

RoarinForeign · 03-01-2019, 03:15 PM

Quote:

Originally Posted by TheGoodTheBadTheUgly

Quote:

Originally Posted by RoarinForeign

You will just have to lower the subframe. It's definitely a doable job but it's a pita. There are a few good YouTube videos and forum posts about the process of the install. My main problem was I didn't take the bracket that holds he thing to the transmission off, after I did that the fat cat slid right out.

Ok good to know. I viewed a video of a N54 subframe lowering I believe, so I do have a slight of an idea of how to do it.

I was searching the forums a bit and on a old downpipe install post some people where saying that they did their xDrivee N55 without even touching the subframe.

Is that even possible?

I remember reading that as well. There's for bolts you loose and it lowers and there's enough space. My main problem was the bracket I didn't take off, once I took that off it slid right off. Getting the o2 sensors off was a pain too, but it's a super rewarding job haha the spool after catlass is awesome

TheGoodTheBadTheUgly · 03-01-2019, 03:23 PM

Quote:

Originally Posted by RoarinForeign

I remember reading that as well. There's for bolts you loose and it lowers and there's enough space. My main problem was the bracket I didn't take off, once I took that off it slid right off. Getting the o2 sensors off was a pain too, but it's a super rewarding job haha the spool after catlass is awesome

Hahaha I am so determined to do that job for many reason, the spool being one haha.

carguy138 · 03-01-2019, 04:46 PM

Quote:

Originally Posted by TheGoodTheBadTheUgly

Hahaha I am so determined to do that job for many reason, the spool being one haha.

Hey any chance you could post some pics or do a mild DIY when you tackle it? There aren't any on the net for an E90 N55 xdrive.

iwantaw335 · 03-01-2019, 07:11 PM

I did mines several years ago. You gotta lower the subframe a bit and you have to get an alignment after! 👎 is it worth it? Not in my opinion.

TheGoodTheBadTheUgly · 03-01-2019, 07:36 PM

Quote:

Originally Posted by carguy138

Hey any chance you could post some pics or do a mild DIY when you tackle it? There aren't any on the net for an E90 N55 xdrive.

Yeah, will do no worries. If I'm searching for some DIY I guess others also would want to have that kind of support.

TheGoodTheBadTheUgly · 03-01-2019, 07:38 PM

Quote:

Originally Posted by iwantaw335

I did mines several years ago. You gotta lower the subframe a bit and you have to get an alignment after! �� is it worth it? Not in my opinion.

Well, my plans are to go with MHD Stage 2 and 2 + and possibly swap for PS2 turbos. So downpipe is like the only remaining bolt on so I can be FBO and be able to support these future mods. I am really decided on doing it.

How much was the alignment if you recall?

Pladi · 03-01-2019, 07:57 PM

Quote:

Originally Posted by iwantaw335

I did mines several years ago. You gotta lower the subframe a bit and you have to get an alignment after! 👎 is it worth it? Not in my opinion.

This is very interesting. Why do you say that ? Just curious. No difference in power ? Or sound ? I mean not much ?

iwantaw335 · 03-03-2019, 01:51 PM

Alignment was about 80 front only.

I did notice sound and slight gain but wasn’t worth all the money spent, PITA install and dealing with smog etc..

Best mod was jb4 which was before downpipe.

Turbod · 03-03-2019, 01:52 PM

Quote:

Originally Posted by TheGoodTheBadTheUgly

Well, my plans are to go with MHD Stage 2 and 2 + and possibly swap for PS2 turbos.

If you're concerned about the install you could wait and do it during the PS2 install. My downpipe is sitting on the shelf until I am ready to swap the turbo.

TheGoodTheBadTheUgly · 03-03-2019, 02:08 PM

Quote:

Originally Posted by Turbod

If you're concerned about the install you could wait and do it during the PS2 install. My downpipe is sitting on the shelf until I am ready to swap the turbo.

Yeah that would be a very wise way to do it, but I am not sure want to directly leap from my current build to PS2.

I was thinking of adding DP, going stage 2+, putting meth injection, then swap turbos if I still want to.

But doing it at the same time as turbos would really be more efficient.

Turbod · 03-03-2019, 02:21 PM

Quote:

Originally Posted by TheGoodTheBadTheUgly

Yeah that would be a very wise way to do it, but I am not sure want to directly leap from my current build to PS2.

I was thinking of adding DP, going stage 2+, putting meth injection, then swap turbos if I still want to.

But doing it at the same time as turbos would really be more efficient.

With my 335i I did each step as most would do. Tune>Chargepipe>Intake>Downpipe>Methanol>Intercool er>PS2. If I were to do it again (I kind of am with the X1) The PS2 would have been done after the tune and intercooler.

MTK24 · 03-04-2019, 12:28 AM

Quote:

Originally Posted by iwantaw335

I did mines several years ago. You gotta lower the subframe a bit and you have to get an alignment after! �� is it worth it? Not in my opinion.

if you need to get an alignment after a downpipe install on x drive then you need to find a better mechanic.

if install is done properly there is no reason to get an alignment. If the mechanic doesn't know what they are doing and moving unnecessary things around then maybe yeah

TheGoodTheBadTheUgly · 03-04-2019, 01:57 AM

Quote:

Originally Posted by Vampire335i

if you need to get an alignment after a downpipe install on x drive then you need to find a better mechanic.

if install is done properly there is no reason to get an alignment. If the mechanic doesn't know what they are doing and moving unnecessary things around then maybe yeah

Did you do yours?

MTK24 · 03-04-2019, 01:59 AM

Quote:

Originally Posted by TheGoodTheBadTheUgly

Quote:

Originally Posted by Vampire335i

if you need to get an alignment after a downpipe install on x drive then you need to find a better mechanic.

if install is done properly there is no reason to get an alignment. If the mechanic doesn't know what they are doing and moving unnecessary things around then maybe yeah

Did you do yours?

I took it to a shop with a lift and watched them install it from start to finish. Took 2 hours. The only hard part was removing o2 sensor from catalytic converter

TheGoodTheBadTheUgly · 03-04-2019, 02:01 AM

Quote:

Originally Posted by Vampire335i

I took it to a shop with a lift and watched them install it from start to finish. Took 2 hours. The only hard part was removing o2 sensor from catalytic converter

Do you recall if they detached the steering rack from the subframe? I guess they would have to. I do all of my works at home so I don't have access to a true lift, only car jack lol.

MTK24 · 03-04-2019, 02:03 AM

Quote:

Originally Posted by TheGoodTheBadTheUgly

Quote:

Originally Posted by Vampire335i

I took it to a shop with a lift and watched them install it from start to finish. Took 2 hours. The only hard part was removing o2 sensor from catalytic converter

Do you recall if they detached the steering rack from the subframe? I guess they would have to. I do all of my works at home so I don't have access to a true lift, only car jack lol.

They dropped the steering rack very little and the subframe very little as well to get the catalytic converter out. Having a lift makes this a 1-2 hour job compares to a 3-4 hour job haha

TheGoodTheBadTheUgly · 03-04-2019, 02:07 AM

Quote:

Originally Posted by Vampire335i

They dropped the steering rack very little and the subframe very little as well to get the catalytic converter out. Having a lift makes this a 1-2 hour job compares to a 3-4 hour job haha

Yeah I really would like to install a lift ~_~. Still good to know that they didn't completely removed it but only lowered a bit! Thanks a lot for the info!

MTK24 · 03-04-2019, 02:11 AM

Good luck! Make sure to use a lot of pb blaster and heat to remove the o2 sensor. It's very tricky because you don't want to use too much force and damage them

TheGoodTheBadTheUgly · 03-04-2019, 02:14 AM

Quote:

Originally Posted by Vampire335i

Good luck! Make sure to use a lot of pb blaster and heat to remove the o2 sensor. It's very tricky because you don't want to use too much force and damage them

Usually, I enjoy the word strip, except when it applies to bolts and screws

Keeping a torch nearby and a lot of penetrative oil!

03-01-2019, 01:06 PM	#1
TheGoodTheBadTheUgly Captain 256 Rep 672 Posts Drives: 2011 E90 335i xDrive Join Date: Feb 2018 Location: Gatineau iTrader: (0)	N55 xDrive Downpipe Install As the title says, I am going to install downpipes for my car soon. The only problem is that's it seems to be a process that is way more hectic than on a RWD 335. So I would like to know, preferably from people who did it on their xDrive 335 or from people who knows about the process, how to install the downpipes. I have heard that you need to drop the subframe in order to access the downpipes mounting point. Does the whole subframe have to come off or you can just lower it a bit? Do you have to remove the steering rack? Any details or insight is appreciated! __________________ TOTALED \| 2011 E90 335i xDrive - BMS Cold Air Intake - ETS Charge Pipe - ETS 7" FMIC - MHD Stage 2+ - GFB DV+ - PE Mod - VRSF Catless Downpipe - xDelete - xHP Stage 3 2015 E84 X1 35i M-Sport
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03-01-2019, 01:59 PM	#2
RoarinForeign Private First Class 36 Rep 120 Posts Drives: 2011 e92 335i xdrive Join Date: Feb 2016 Location: Western MA iTrader: (0)	You will just have to lower the subframe. It's definitely a doable job but it's a pita. There are a few good YouTube videos and forum posts about the process of the install. My main problem was I didn't take the bracket that holds he thing to the transmission off, after I did that the fat cat slid right out.
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03-01-2019, 07:11 PM	#7
iwantaw335 Second Lieutenant 22 Rep 220 Posts Drives: 2015 320i Join Date: Sep 2010 Location: Mission Viejo iTrader: (2)	I did mines several years ago. You gotta lower the subframe a bit and you have to get an alignment after! 👎 is it worth it? Not in my opinion.
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03-03-2019, 01:51 PM	#11
iwantaw335 Second Lieutenant 22 Rep 220 Posts Drives: 2015 320i Join Date: Sep 2010 Location: Mission Viejo iTrader: (2)	Alignment was about 80 front only. I did notice sound and slight gain but wasn’t worth all the money spent, PITA install and dealing with smog etc.. Best mod was jb4 which was before downpipe.
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03-04-2019, 02:11 AM	#21
MTK24 Lieutenant 485 Rep 599 Posts Drives: 2011 335I X Drive Join Date: Nov 2017 Location: Seattle iTrader: (0)	Good luck! Make sure to use a lot of pb blaster and heat to remove the o2 sensor. It's very tricky because you don't want to use too much force and damage them __________________ Vermillion Red
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