[otitxn]

Alright all, I have a set of AA headers for my 328xi LCI. I am looking into getting them installed, and have run into a few questions. Do I need to drop or lower the subframe in order to do the job? I've been looking for install guides, and all I can find are for the regular RWD 328i's. All help and feedback is immensely appreciated!

[W37V]

No

[otitxn]

Originally Posted by W37V

No

Okay, wanna help link install guides or anything of the sort? “No,” albeit an answer to my question, was not very helpful.

[W37V]

Originally Posted by otitxn

Okay, wanna help link install guides or anything of the sort? “No,” albeit an answer to my question, was not very helpful.

I’m confused as why are you still asking for more.

So... have you opened the hood of your car? Have you examined where headers are going? Have you compared them with instructions posted on here? Are there any differences between instructions given and your vehicle? What are the differences?

Your post tells me that you did nothing listed above. If you did, you would’ve noticed that it’s all the same regardless of the drive, or transmission.

Here are instructions (the ones you found are probably better and more detailed than this):
Stop freaking out
It’s gonna take you 4 hours first time you do it
Open hood
Remove bunch of plastic pieces for easier access to the headers
Move your coolant reservoir
Unscrew 16 or 18 bolts
Remove old headers
Swap out o2 sensors from old into new so you don’t fuck up position of sensors
Put in new headers
Button up everything
Flash the tune
Enjoy

[E92William]

I believe it is a bit tighter of a job on the xdrive cars but should be perfectly doable.

As per RealOEM the front exhaust manifold that serves cylinder 1-3 on the xdrive cars has a different part number than the rwd cars. The rear one seems to be shared.

I researched the two part numbers and there seem to be no visual differences. Also I wouldn't worry too much since the headers are not as bulky as the stock system.

[3002 tii]

Originally Posted by W37V

I’m confused as why are you still asking for more.

So... have you opened the hood of your car? Have you examined where headers are going? Have you compared them with instructions posted on here? Are there any differences between instructions given and your vehicle? What are the differences?

Your post tells me that you did nothing listed above. If you did, you would’ve noticed that it’s all the same regardless of the drive, or transmission.

Here are instructions (the ones you found are probably better and more detailed than this):
Stop freaking out
It’s gonna take you 4 hours first time you do it
Open hood
Remove bunch of plastic pieces for easier access to the headers
Move your coolant reservoir
Unscrew 16 or 18 bolts
Remove old headers
Swap out o2 sensors from old into new so you don’t fuck up position of sensors
Put in new headers
Button up everything
Flash the tune
Enjoy

I’m thinking 6-8 hours...

[matteblue3er]

I lowered my subframe for extra clearance. Could probably do it without doing so but it made it much easier to get them in and out. It's about 9 bolts I think, 6 subframe, 2 steering rack, 1 coolant line bracket by sway bar.

Used engine support brace from the top. Hung subframe from suspension.

Took ~6 hours

Some things to consider....

1) Replace 02s if nearing or past 100k miles. I was at 132k and just slapped new ones in even though I didn't have any issues
2) Consider motor mounts if you lower subframe, especially passenger side

I did not have to move my coolant tank, not sure why this was mentioned.
Tape or mark 02 connectors so you know which goes to which when reinstalling.

[otitxn]

Thank you all for your input, I will attempt this myself in the near future as most shops want around $700-900 to do this

[W37V]

Originally Posted by matteblue3er

I lowered my subframe for extra clearance. Could probably do it without doing so but it made it much easier to get them in and out. It's about 9 bolts I think, 6 subframe, 2 steering rack, 1 coolant line bracket by sway bar.

Used engine support brace from the top. Hung subframe from suspension.

This is an overkill. Unless you are doing something else, there is no need to do this.

Took ~6 hours

Sounds about right. After doing this job ~6+ times, I got it down to about 2 hours.

Some things to consider....

1) Replace 02s if nearing or past 100k miles. I was at 132k and just slapped new ones in even though I didn't have any issues
2) Consider motor mounts if you lower subframe, especially passenger side

If you are dropping subframe, might as well do oil pan gasket etc. But at that point, you are no longer doing headers. You are doing everything else but headers.

I did not have to move my coolant tank, not sure why this was mentioned.

If you are unbolting headers from the above, you need extra elbow clearance to maneuver around.

Tape or mark 02 connectors so you know which goes to which when reinstalling.

Good advice

[matthewjmoser]

The mount was cut I believe it’s number 10 on the diagram. And the headers were actually pulled through the top on my 328xi for some aa headers.

[matteblue3er]

Originally Posted by W37V

This is an overkill. Unless you are doing something else, there is no need to do this.

Sounds about right. After doing this job ~6+ times, I got it down to about 2 hours.

If you are dropping subframe, might as well do oil pan gasket etc. But at that point, you are no longer doing headers. You are doing everything else but headers.


If you are unbolting headers from the above, you need extra elbow clearance to maneuver around.

Good advice

I used an air ratchet so maybe that's why I didn't need clearance.

The oil pan requires axle removal. I wouldn't tackle that at the same time if the OP is asking questions.

[The Nightman]

Not a difficult job by any means but tedious. It's a battle of ergonomics and access. 6 hours is about right as you waste a lot of time figuring out how to access the nuts, and backing the nuts off as the studs are quite long.

I found plenty of guides and tips when searching, but here's some more info based on my experience on a RWD:

- need 1/4" and 3/8" drive deep sockets and 1" to 4" extensions. 3/8" works for most, but I needed 1/4" for the front two nuts. A swivel-head ratchet was nice to have but not necessary. Higher toothcount help due to the limited space.
- lift the car high enough so that you're not bending a lot.
- put the hood into "service position" by removing the hood struts and propping the hood up ~90°. There are stops to prevent it from going further.
- relocating coolant reservoir is easy and gives you more access.
- penetrating fluid on the studs makes backing the nuts off a lot easier. I needed a long straw (1-2') to get to most of the studs.
- label O2 sensors so that they do not get mixed up. I removed the primaries first and the secondaries (needed a flare wrench) after lowering the headers.
- you may want to consider replacing the primary O2 sensors at the same time as they will be a lot harder to access on the AA headers. Replace the B2 sensor with a B1 sensor due to its longer cable. Use antiseize!
- I was able to remove all manifold nuts from the engine bay. During reinstallation, I found it easier to do the back 2 nuts from below.
- remove midpipe brace from transmission to lower exhaust and remove the headers. B2 fell out first on their own, B1 needed some persuasion.
- check and clean the exhaust ports as the manifold gaskets can separate.

Good luck. It's very straightforward and easier than it looks. I had more trouble replacing my waterpump and thermostat. The stock headers are worth a decent amount (~$250) at recyclers if you don't need them anymore.

[otitxn]

So thanks to everyone, the install went okay. However, I now have a very loud and present ticking noise when I start the car and when I accelerate. The car is not tuned, and will be on Tuesday by Bob at Stage FP (formerly worked are BPC). Any idea what the ticking could be, and how to fix it? Thank you in advance for all of your help, you were all instrumental in me tackling this job myself

[W37V]

Originally Posted by otitxn

So thanks to everyone, the install went okay. However, I now have a very loud and present ticking noise when I start the car and when I accelerate. The car is not tuned, and will be on Tuesday by Bob at Stage FP (formerly worked are BPC). Any idea what the ticking could be, and how to fix it? Thank you in advance for all of your help, you were all instrumental in me tackling this job myself

Describe ticking? Where does it come from? How does it sound? Is it rattle? Is it exhaust leak? Is it coming from the engine?

How long was car sitting? Did you check all the wires if you plugged them right? Are you sure you didn’t have ticking before?

The reason I’m asking this is: headers would not have anything to do with anything on the engine. Typically, after installing any modifications we tend to be super observant. Your ticking may have been present before, but you never noticed it cuz you were not paying attention to it. Now you noticed it and will keep hearing it.

Other possibility is that your car was sitting too long so all oil drained from lifters. Few redline shifts would take care of that. Another possibility is that you have an exhaust leak. Did you tighten everything well? Double check it.

And final question- were there any differences between your install and instructions posted on rwd cars?

[PhaseP]

I had removed and installed mine for some work, and i have 325xi. I had to to lower the subframe, there wasn't enough clearance for them to come out. You can remove all the bolts and such, but subframe is in the way to take them out. If anyone could remove them without lowering subframe on an n52 xi you are a better puzzle solver than i am. If living in rust belt, header nuts will take the studs out, or worse break them, not fun.
I am talking about oem ones btw, catless may cone out due to not having the bulky cats.

[E92William]

Originally Posted by PhaseP

I had removed and installed mine for some work, and i have 325xi. I had to to lower the subframe, there wasn't enough clearance for them to come out. You can remove all the bolts and such, but subframe is in the way to take them out. If anyone could remove them without lowering subframe on an n52 xi you are a better puzzle solver than i am. If living in rust belt, header nuts will take the studs out, or worse break them, not fun.
I am talking about oem ones btw, catless may cone out due to not having the bulky cats.

Dude you're scaring me I'll literally chop these exhaust manifolds in half with a sawzall before I drop that subframe down on my 328xi

[otitxn]

Originally Posted by W37V

Describe ticking? Where does it come from? How does it sound? Is it rattle? Is it exhaust leak? Is it coming from the engine?

How long was car sitting? Did you check all the wires if you plugged them right? Are you sure you didn’t have ticking before?

The reason I’m asking this is: headers would not have anything to do with anything on the engine. Typically, after installing any modifications we tend to be super observant. Your ticking may have been present before, but you never noticed it cuz you were not paying attention to it. Now you noticed it and will keep hearing it.

Other possibility is that your car was sitting too long so all oil drained from lifters. Few redline shifts would take care of that. Another possibility is that you have an exhaust leak. Did you tighten everything well? Double check it.

And final question- were there any differences between your install and instructions posted on rwd cars?

Okay, so the sound is hard to describe so I took a video and uploaded it to youtube here:

. I'm hoping it's an exhaust leak, because upon a visual inspection while recording that video I am missing a stud on the front header. The noise is the rapid “tick tick tick tick”, was NEVER present prior to the install.

Wires are all installed correctly, I triple checked and used a paint marker on the connectors, and a pad of paper to correctly identify which O2 sensor goes where.

I am positive I haven't had the ticking before, I had no sounds from the engine bay prior. All the connections down low are secure with gaskets and the new provided hardware. I tried driving it home yesterday from my buddies garage (had a lift which helped IMMENSELY) and the ticking happens when you accelerate, as well as idle. I also tried giving it a ton of high RPM revs to help with the oil drain potential solution, no dice.

Lastly, the install took about 8-9 hours straight, give or take. The install was fairly straight forward. Moved the coolant reservoir out of the way, undid some brackets on the head holding wires, and jammed my hands in with an angled rotating head ratchet. Hardest part was removing the stock manifolds. Had to undo the hardware, maneuver the manifold so I could reach up and in from underneath with a sawzall to cut the isolator off the front bank. That was the only thing preventing the removal of the stock manifolds. From there, I removed the front set and then the rear set. Installation of the new ones provided a ton more space than the stock set. However, I needed to slide the rears in first, then the fronts and then bolt everything up last. I made it harder on myself to install the O2 sensors after the headers were bolted back up, I don't recommend that.