[e90nestor]

I got some downpipes i need to re install on my car anyone know of a good spot in the Bay Area to get them done at a couple shops told me i have to bring the car in a trailer and take it out in a trailer cause they are catless

[Nastymateo]

Do it yourself. It's not really that hard. You trying to pass smog? I take mine off every 2 years for a week to pass smog.

[malgyver]

I've had luck using the DP fix, and not taking my pipes off. You probably won't find a shop to do this for you, because its illegal to remove cats.

I would try to convince someone here to help you out, or just learn to do it yourself if you have some basic tool skills. And tools! At the very least, you'll need a jack, a couple of jack stands, and some balls to be able to get under the car, on your back, to do this job. As well, remember that when its smog time, you will either need to put the cats back on, or locate a DP fix, which is a little electronic module, and install that/mess with it to make things work and look like the cats are still on to the smog machine.

[Milan]

If your car is RWD it's pretty easy. If it's AWD it's not too bad but not fun either.

[e90nestor]

Thanks for help!!I went out and got some tools i was missing 🔧going to try it out this weekend

[mweisdorfer]

Originally Posted by e90nestor

I got some downpipes i need to re install on my car anyone know of a good spot in the Bay Area to get them done at a couple shops told me i have to bring the car in a trailer and take it out in a trailer cause they are catless

If the car has seen Salt or harsh winters like in the mid-west or NE, then it will be a major PITA getting the OEM cats off. However, if that's not the case, I agree with the above posters, shouldn't be too bad on 4 jack-stands with the right set of tools. Just make sure you get replacement gaskets & bolts. Maybe get some Nickel based anti-seize for the exhaust bolts & V clamps on the turbo to down pipe connection. That will make getting them off next tine a whole lot easier.

[N54Society]

How did it go?

[DM_e92]

I dont know about the OP, but I installed some DPs on the New years day. Pain in the ass to get the V band clamps to set perfect. I got a couple question for some people though, after I put on the Downpipes I could feel the idle throughout the car a lot more making me think I might need to go under and re adjust or something. Is this normal? Also I knew I would be able to hear my turbos more, but The new turbo noise is high pitched and almost like a whistle, is that normal? I Have Newer OEM turbos with about 10,000 miles on them so I dont think its anything with the turbos. What you guys think?

[Silent9n54]

Originally Posted by DM_e92

I dont know about the OP, but I installed some DPs on the New years day. Pain in the ass to get the V band clamps to set perfect. I got a couple question for some people though, after I put on the Downpipes I could feel the idle throughout the car a lot more making me think I might need to go under and re adjust or something. Is this normal? Also I knew I would be able to hear my turbos more, but The new turbo noise is high pitched and almost like a whistle, is that normal? I Have Newer OEM turbos with about 10,000 miles on them so I dont think its anything with the turbos. What you guys think?

first time a shop installed my downpipes i was getting a ton of vibration at idle, it was shaking my door panels... shop told me its because my motor mounts are old and the engine is sagging and the pipes are hitting the body... 2 weeks later i replaced the motor mounts and the idle vibration was gone... but now when i turn left i can hear it rub again... shop says downpipes cant be moved around or adjusted so im kinda stuck with this annoying noise...

[N54Society]

Originally Posted by shanker604

first time a shop installed my downpipes i was getting a ton of vibration at idle, it was shaking my door panels... shop told me its because my motor mounts are old and the engine is sagging and the pipes are hitting the body... 2 weeks later i replaced the motor mounts and the idle vibration was gone... but now when i turn left i can hear it rub again... shop says downpipes cant be moved around or adjusted so im kinda stuck with this annoying noise...

Sounds like a faulty installer.

[Silent9n54]

Originally Posted by vbp6us

Sounds like a faulty installer.

its a reputable shop, they've built racecars and engines from scratch i wouldnt think this would cause them problems. So the question is can you move them around a bit to make them fit better or not ?

[LMB335IS]

Originally Posted by shanker604

first time a shop installed my downpipes i was getting a ton of vibration at idle, it was shaking my door panels... shop told me its because my motor mounts are old and the engine is sagging and the pipes are hitting the body... 2 weeks later i replaced the motor mounts and the idle vibration was gone... but now when i turn left i can hear it rub again... shop says downpipes cant be moved around or adjusted so im kinda stuck with this annoying noise...

They can be rotated a small amount to insure clearance. They shouldn't touch anything if properly installed, especially with new mounts.

[feuer]

Originally Posted by LMB335IS

They can be rotated a small amount to insure clearance. They shouldn't touch anything if properly installed, especially with new mounts.

That is true, however it might cause issue lining them up with with the exhaust. When done this way they either pull or push on the turbo housing. What I do is place a washer between engine mount and engine to space them up. Essentially you are raising the engine few millimeters which is usually enough to clear any interference between pipes and subframe. Sometimes I even replace the side bolt on the engine mount bracket. All depends from the pipes.

[Silent9n54]

its slowly driving me crazy... overall my car is super quiet... no rattles or squeaks, still stock exhaust...but i hate turning left now lol

[feuer]

Originally Posted by shanker604

its slowly driving me crazy... overall my car is super quiet... no rattles or squeaks, still stock exhaust...but i hate turning left now lol

Follow my suggestions...

Originally Posted by shanker604

its a reputable shop, they've built racecars and engines from scratch i wouldnt think this would cause them problems. So the question is can you move them around a bit to make them fit better or not ?

If they have little/no experience with the N54 or this platform, all that experience means nothing when it comes to solving your problem.

[DM_e92]

https://photos.app.goo.gl/1uXrSuHE1UJERKNv7

For my install, I think it may be the Down pipe Flanges touching each other. I will attach a pic of what I'm am talking about. I should be able to adjust them slightly so they don't touch??

[LMB335IS]

Originally Posted by DM_e92

https://photos.app.goo.gl/1uXrSuHE1UJERKNv7

For my install, I think it may be the Down pipe Flanges touching each other. I will attach a pic of what I'm am talking about. I should be able to adjust them slightly so they don't touch??

You should be able to get enough clearance between the flanges so that they don't touch. You'll need to loosen the V-bands a bit and try to twist them a little to get that 1/4-1/2 inch of clearance. Loosen the the flange bolts too so that everything has a bit of play, get it all it the right position, then start tightening it all back up making sure it doesn't move in the process. Results may vary but it works for me.

[DM_e92]

Originally Posted by LMB335IS

You should be able to get enough clearance between the flanges so that they don't touch. You'll need to loosen the V-bands a bit and try to twist them a little to get that 1/4-1/2 inch of clearance. Loosen the the flange bolts too so that everything has a bit of play, get it all it the right position, then start tightening it all back up making sure it doesn't move in the process. Results may vary but it works for me.

Thanks for the suggestion, I was a lil confused if the car should idle like this as my friends 135i with downpipes and full flow exhaust does idle like this, I still have my secondary cats and Muffler, He does not. I'm going to try and re adjust this week when I get a chance.

[Austins]

I just had a shop install downpipes on my e90 yesterday... well safe to say they messed up.
Took it for a drive, the turbos are rattling like crazy! (brand new stock turbos installed by them 3 months ago) and only making 2psi boost... guessing the vband clamp bolt is obstructing the wastegate arm or something. They're looking tomorrow under warranty.
They managed to get 10mm clearance with the downpipe to the body luckily

Asked them to tighten the rods too as i had turbo rattle accelerating before the install and they said they are tight as ever with no play... think i need a new shop haha

[feuer]

Austins all OEM designed turbos will rattle even brand new and downpipes will make that more obvious since catalytic converters will muffle the rattle. I have posted videos on here to support this. Regarding not making boost post downpipes installation could be an interference as you said or incidentally disconnected vacuum line. I hope it will be a quick fix.

[vinhlai]

I'm here trying to pass inspection with catless dp and a dp fix