[olivojoe]

I ordered one today since their black friday sale was still on, and I am trying to find a how to video for installing on the N55. I searched the DIY threads and youtube, but all I could come up with was a video for the N54. Will this video be good enough or are there major differences that will make this video useless? (other than going from two pipes for the N54 to the one pipe for the N55)

If anyone could point me to a good how to that would be awesome. Thanks.

[mpls_M3]

Heres a DIY guide from cobb.

http://www.oakos.com/product_docs/COB-5B2202.pdf

[Jsoboti]

there is not a video available, however there are multiple threads about this with advice and tips and tricks. just search around some more

[Tiago@VRSF]

That write-up will work just fine

[jwalker87]

I just hope you don't have x-drive. I just installed a DP on my wife's xi yesterday, and man was that a pain...

[TeinBMW]

Originally Posted by jwalker87

I just hope you don't have x-drive. I just installed a DP on my wife's xi yesterday, and man was that a pain...

+1

I hear yah brother. Wasn't fun at all

[olivojoe]

Originally Posted by jwalker87

I just hope you don't have x-drive. I just installed a DP on my wife's xi yesterday, and man was that a pain...

Yes I am xDrive, what is difficult about it?


Thanks for all the replies, I will post any of my advice I gain from the job once I get it on.

[olivojoe]

Originally Posted by ihazvtak

Heres a DIY guide from cobb.

http://www.oakos.com/product_docs/COB-5B2202.pdf

Thanks, that write up is the best I've seen so far. I can only hope it goes as smooth as that write up makes it seem to be. Now I'm just curious to hear what these other guys are saying that makes the xDrive so much more of a pain.

[jwalker87]

Installation on my 335i: Unbolt exhaust from DPs, remove hanger, remove V-bands and o2 sensors, replace

335xi: All of the above, but you also have to unbolt the engine mounts from the subframe, remove some more plastic around the wheel wells, support the engine with a jack, support the subframe with another jack, remove the 6 subframe bolts one side at a time to drop the subframe ~6" so you can get the DP out.

Bottom line, the room that you would use to get to the DP is now taken up by axle and differential/xfer case/whatever.

[tke344]

Originally Posted by jwalker87

Installation on my 335i: Unbolt exhaust from DPs, remove hanger, remove V-bands and o2 sensors, replace

335xi: All of the above, but you also have to unbolt the engine mounts from the subframe, remove some more plastic around the wheel wells, support the engine with a jack, support the subframe with another jack, remove the 6 subframe bolts one side at a time to drop the subframe ~6" so you can get the DP out.

Bottom line, the room that you would use to get to the DP is now taken up by axle and differential/xfer case/whatever.

On your RWD car, did you actually need to unbolt the steering rack? The Cobb instructions say to do so but I've read elsewhere that it wasn't necessary. I planned on doing the install on ramps so I really wouldn't be able to turn the wheels once it's up.

[Jsoboti]

Originally Posted by tke344

On your RWD car, did you actually need to unbolt the steering rack? The Cobb instructions say to do so but I've read elsewhere that it wasn't necessary. I planned on doing the install on ramps so I really wouldn't be able to turn the wheels once it's up.

Negative, RWD do not have to remove anything major.

That being said, I removed the engine mount to make it easier, hard to do without a lift and a trans jack though.

[olivojoe]

Originally Posted by jwalker87

Installation on my 335i: Unbolt exhaust from DPs, remove hanger, remove V-bands and o2 sensors, replace

335xi: All of the above, but you also have to unbolt the engine mounts from the subframe, remove some more plastic around the wheel wells, support the engine with a jack, support the subframe with another jack, remove the 6 subframe bolts one side at a time to drop the subframe ~6" so you can get the DP out.

Bottom line, the room that you would use to get to the DP is now taken up by axle and differential/xfer case/whatever.

Bad news for me then, I'm not going to have the equipment to be able to do all of that. Looks like I'll be hunting someone down to have this done.


Has anyone had experience with asking the dealership to do this? Will they install a catless downpipe? I am in FL so there are no emissions tests.

[Jsoboti]

Originally Posted by olivojoe

Bad news for me then, I'm not going to have the equipment to be able to do all of that. Looks like I'll be hunting someone down to have this done.


Has anyone had experience with asking the dealership to do this? Will they install a catless downpipe? I am in FL so there are no emissions tests.

You would probably have better luck getting the dealer to give you a free car .

Go to an indy to have it done, or get on the regional board and see if anyone in your area has done it and would be willing to lend a hand.

[Jacblack]

Xdrive is a true PITA especially the first time around.

[4lss]

I've done this swap on my 2011 335xi sedan. Didn't have to remove motor mounts nor drop the subframe. Took me about 4 hrs on jack stands and no power tools. Make sure to hit the exhaust to DP bolts with Freeze-off or the likes. You will definitely need a O2 sensor with flex head, all kinds of ratchet extensions, universal joints and a WHOLE lot of patience.

[jwalker87]

Originally Posted by djfellipe

I've done this swap on my 2011 335xi sedan. Didn't have to remove motor mounts nor drop the subframe. Took me about 4 hrs on jack stands and no power tools. Make sure to hit the exhaust to DP bolts with Freeze-off or the likes. You will definitely need a O2 sensor with flex head, all kinds of ratchet extensions, universal joints and a WHOLE lot of patience.

Just out of curiosity, how did you physically get the DP out of the car? I tried this for a few hours before breaking down and doing what all my research told me I had to do ... drop the subframe. It had nothing to do with accessing bolts or anything. There was physically not enough room to remove the DP with the subframe in place. It would have taken much less time if I'd just done that from the beginning.

[4lss]

Originally Posted by jwalker87

Just out of curiosity, how did you physically get the DP out of the car? I tried this for a few hours before breaking down and doing what all my research told me I had to do ... drop the subframe. It had nothing to do with accessing bolts or anything. There was physically not enough room to remove the DP with the subframe in place. It would have taken much less time if I'd just done that from the beginning.

It came right off as soon as I removed the mid-pipes bracket and moved the pipes to the side. I also had the o2 sensors removed at this point, I don't think the DP would come out with the o2 sensors attached to it.

[DevonD]

I just installed a BMS downpipe last night on my E90 xDrive and DID NOT drop the subframe or take the axle off or do any of the extra stuff people have said needs to be done. The only additional part I took off was the actual bracket that the stock DP mounts to. I took off the DP to the bracket bolts like you would normally do and then took out the two bracket bolts and removed it. Then the DP slid right out. Both 02 sensors still in place as well. It took about 2 1/2 - 3 hours to complete the whole thing.

[Johnny Boost]

Originally Posted by olivojoe

Bad news for me then, I'm not going to have the equipment to be able to do all of that. Looks like I'll be hunting someone down to have this done.


Has anyone had experience with asking the dealership to do this? Will they install a catless downpipe? I am in FL so there are no emissions tests.

I asked mine to do it but they quoted me $700-800 in labor for the install so I went elsewhere.

[iuhutch]

Originally Posted by Johnny Boost

I asked mine to do it but they quoted me $700-800 in labor for the install so I went elsewhere.

Any legit German mechanic/shop should do these all day for <$300...

[4lss]

Originally Posted by DevonD

I just installed a BMS downpipe last night on my E90 xDrive and DID NOT drop the subframe or take the axle off or do any of the extra stuff people have said needs to be done. The only additional part I took off was the actual bracket that the stock DP mounts to. I took off the DP to the bracket bolts like you would normally do and then took out the two bracket bolts and removed it. Then the DP slid right out. Both 02 sensors still in place as well. It took about 2 1/2 - 3 hours to complete the whole thing.

I decided to take the o2 sensor while attached to turbo. That was a PITA. Worst part of the installation.
Next time I'll try unplugging the o2 sensor connectors and leave them on the DP.

[DevonD]

Originally Posted by djfellipe

I decided to take the o2 sensor while attached to turbo. That was a PITA. Worst part of the installation.
Next time I'll try unplugging the o2 sensor connectors and leave them on the DP.

Taking the lower one off would have made it a little easier to get out but removing that bracket was by far the biggest part of taking the DP out easily. I have no idea how you removed the upper o2 sensor with the DP on the turbo! I'm impressed!