[E90Company]

Bump for a conclusion.

[KaiserN54]

Originally Posted by E90Company

Bump for a conclusion.

Well, I took it a "friendly" dealer. I call them that because they know I have mods, have looked at the car for me despite that, and are generally interested in how the car performs. Despite this, they wouldnt do the wastegate warranty for me because, as they claimed- they have knowledge of the mods and didn't want to get caught doing the warranty work. They are the ones who suggested de-mod-ing and going to a different dealer.


Anyways, I brought it to them for an opinion. The foreman agreed something is definately "going on" with them, and reminded me that I have a two year warranty on the parts. With that in mind, he said that if they are performing, and not blowing smoke, I might wait until it gets worse before taking everything off the car and going back to the installing dealer.

Heres the scary thing- he went on to say that the warranty will cover incidental damage as well- implying that, if the turbos grenade- they might well take the motor with them!!

As far as performance, I talked to shiv and my issues- being entirely fuel related, as the logs show, is more or less a matter of resetting my adaptations and staying OUT of map 0, which screws everything up. I haven't driven quite enough miles to test this out, but thus far the car seems much stronger and consistent. In sum, the performance issues I was experiencing off and on may be entirely unrelated to the turbos.

This brings me to the question of what to do with regards to the turbos. Wait, or de-mod and bring it to BMW now? If I de-mod, do I go as far as sending the DME back to Shiv for a flash back to stock? Or do I assume the dealer won't notice that the car is only making 1-2lbs of boost when being driven?

My daughter, who was born only a week ago, will be old enough to drive this car before I finally get everything on it sorted out.

[A418t81]

I'd be surprised if they do anything. What you are hearing is turbo bearing noise. It happens to most N54s that are tuned, but the occasional stock car will have it too. It's not "normal" in the sense that they don't do this stock generally, but most tuned cars will end up with a little bearing noise. It's a very, very common complaint and one that WILL come back if you remod your car after the turbos are replaced. It doesn't appear to have any correlation with actual damage to the CHRA, and there's no issues with oil leakage, or decreased performance as a consequence.

Many on the forum have complained of the same "problem" and the vast majority have been turned away by the dealership. I have yet to see one have a real issue that was heralded by the noise.

As far as the car not feeling as fast, I bet you are just becoming accustomed to the power, as happens to all of us, or potentially there is some other issue unrelated to your bearing noise.

[KaiserN54]

Originally Posted by A418t81

I'd be surprised if they do anything. What you are hearing is turbo bearing noise. It happens to most N54s that are tuned, but the occasional stock car will have it too. It's not "normal" in the sense that they don't do this stock generally, but most tuned cars will end up with a little bearing noise. It's a very, very common complaint and one that WILL come back if you remod your car after the turbos are replaced. It doesn't appear to have any correlation with actual damage to the CHRA, and there's no issues with oil leakage, or decreased performance as a consequence.

Many on the forum have complained of the same "problem" and the vast majority have been turned away by the dealership. I have yet to see one have a real issue that was heralded by the noise.

As far as the car not feeling as fast, I bet you are just becoming accustomed to the power, as happens to all of us, or potentially there is some other issue unrelated to your bearing noise.

I've heard bearing noise before on my old turbos and my other 335i I used to own. This noise is more of a whistle, a drill, a police siren. I only hear it at street level speeds and RPM's. Doesn't really improve even when the car is warmed up. Is this just the same as turbo bearing noise, or does it sound different? Can different turbos have distinctly different bearing noises?

[Evil///M]

Ive got brand new turbos as well, only 1k on them and they are already starting to rattle on cold startup, and with load.

[Drawn05]

Originally Posted by atomos319

As far as performance, I talked to shiv and my issues- being entirely fuel related, as the logs show, is more or less a matter of resetting my adaptations and staying OUT of map 0, which screws everything up.

Sorry for OT, but what exactly is meant by this? Is not using map 0 recommended for all procede users or is it something to do with the flex fuel flash?

I often use map 0 when i heavy traffic etc. but should I just reset all adaptations and leave it in map 2?

[KaiserN54]

Originally Posted by Drawn05

Sorry for OT, but what exactly is meant by this? Is not using map 0 recommended for all procede users or is it something to do with the flex fuel flash?

I often use map 0 when i heavy traffic etc. but should I just reset all adaptations and leave it in map 2?

I think only flex-fuel, but I could be wrong.

[A418t81]

Originally Posted by atomos319

I've heard bearing noise before on my old turbos and my other 335i I used to own. This noise is more of a whistle, a drill, a police siren. I only hear it at street level speeds and RPM's. Doesn't really improve even when the car is warmed up. Is this just the same as turbo bearing noise, or does it sound different? Can different turbos have distinctly different bearing noises?

Yep, the bearing noise that isn't bad is the kind you are showing in your videos that you only hear at very light loads, and low speeds. Once you get up above about 4 psi, it goes away. The dentist drill sound that sticks around and gets louder the faster the turbos spin is the "bad" kind. Yes, the turbos can sound different than your other sets. I have a buddy with a '11 335iS that sounds like a mac truck when it's cold though it improves as it heats up, it's still very noticeable at low speeds and light loads. Learn to ignore it and be happy with the performance of your car. At 21 psi in the midrange, your shaft speeds are very, very high...the turbos are going to make a little bearing noise, that's the life of a highly modded stock turbo car.

[E90Company]

Originally Posted by A418t81

Yep, the bearing noise that isn't bad is the kind you are showing in your videos that you only hear at very light loads, and low speeds. Once you get up above about 4 psi, it goes away. The dentist drill sound that sticks around and gets louder the faster the turbos spin is the "bad" kind. Yes, the turbos can sound different than your other sets. I have a buddy with a '11 335iS that sounds like a mac truck when it's cold though it improves as it heats up, it's still very noticeable at low speeds and light loads. Learn to ignore it and be happy with the performance of your car. At 21 psi in the midrange, your shaft speeds are very, very high...the turbos are going to make a little bearing noise, that's the life of a highly modded stock turbo car.

And turbo's that were designed to be put on motorcycles. These turbo's spin fast all the time

[cn555ic]

Originally Posted by E90Company

And turbo's that were designed to be put on motorcycles. These turbo's spin fast all the time

BMW wanted as little lag as possible and power at 1400-1500 rpms is pretty awesome

[A418t81]

Originally Posted by E90Company

And turbo's that were designed to be put on motorcycles. These turbo's spin fast all the time

I'm not sure what you mean by your post or if you are trying to be elementary, but I'm here to tell you that just because turbos "spin fast all the time" means nothing as related to the amount of boost we are running on this platform now.

A little about how turbos are built: A turbo has a range of rpm in which it is specified to operate in by the manufacturer. In the case of our tiny little guys, they are probably rated up to somewhere around 200,000 rpm. Yep, you read that right. What this means, is that mitsu takes the maximum rpm they've rated the turbo for into account when they balance the spinning assembly. Obviously the faster you spin something, the more apparent imbalances become and the more stress it puts on it's bearings, wearing them a bit unevenly. Same thing applies here. We are spinning the CRAP out of these things, and there's going to be a little bit of bearing complaints as a result. People "overspin" stock turbos on basically every platform where modding is a possibility, some overspin more than others. The stock mitsus appear to be very resistant to essentially having the kitchen sink thrown at them. The borg-warner turbos on the VW/Audi 4 cylinders are also very resistant to being spun up WAY over their rated rpm values. I guarantee you that if you kept your boost pressure to around 12-13 psi max, the turbos would remain silent.

[KaiserN54]

Originally Posted by A418t81

I'm not sure what you mean by your post or if you are trying to be elementary, but I'm here to tell you that just because turbos "spin fast all the time" means nothing as related to the amount of boost we are running on this platform now.

A little about how turbos are built: A turbo has a range of rpm in which it is specified to operate in by the manufacturer. In the case of our tiny little guys, they are probably rated up to somewhere around 200,000 rpm. Yep, you read that right. What this means, is that mitsu takes the maximum rpm they've rated the turbo for into account when they balance the spinning assembly. Obviously the faster you spin something, the more apparent imbalances become and the more stress it puts on it's bearings, wearing them a bit unevenly. Same thing applies here. We are spinning the CRAP out of these things, and there's going to be a little bit of bearing complaints as a result. People "overspin" stock turbos on basically every platform where modding is a possibility, some overspin more than others. The stock mitsus appear to be very resistant to essentially having the kitchen sink thrown at them. The borg-warner turbos on the VW/Audi 4 cylinders are also very resistant to being spun up WAY over their rated rpm values. I guarantee you that if you kept your boost pressure to around 12-13 psi max, the turbos would remain silent.

Well, I get whine even when on map 0...1-2 lbs of boost, likely below stock spin speeds. And you noted above 4 PSI it goes away... not sure of the relationship between PSI and how fast they are spinning, but just because I make 21 PSI midrange, why would they scream under much lower boost? BTW the pitch of the siren goes up the faster they spin until I can't hear it.... usually above 3500.

[E90Company]

Originally Posted by A418t81

I'm not sure what you mean by your post or if you are trying to be elementary, but I'm here to tell you that just because turbos "spin fast all the time" means nothing as related to the amount of boost we are running on this platform now.

A little about how turbos are built: A turbo has a range of rpm in which it is specified to operate in by the manufacturer. In the case of our tiny little guys, they are probably rated up to somewhere around 200,000 rpm. Yep, you read that right. What this means, is that mitsu takes the maximum rpm they've rated the turbo for into account when they balance the spinning assembly. Obviously the faster you spin something, the more apparent imbalances become and the more stress it puts on it's bearings, wearing them a bit unevenly. Same thing applies here. We are spinning the CRAP out of these things, and there's going to be a little bit of bearing complaints as a result. People "overspin" stock turbos on basically every platform where modding is a possibility, some overspin more than others. The stock mitsus appear to be very resistant to essentially having the kitchen sink thrown at them. The borg-warner turbos on the VW/Audi 4 cylinders are also very resistant to being spun up WAY over their rated rpm values. I guarantee you that if you kept your boost pressure to around 12-13 psi max, the turbos would remain silent.

Not sure where you got elementary from my post. Anyhow...

Point was, when you have small turbo's on a car designed for the engine displacement of a motorcycle (TD03), they are going to be constantly spinning at a higher RPM when cruising than a bigger compressor, no matter what. You are talking about overspinning with higher boost; I'm talking about turbo's spinning at a higher RPM on a daily basis. This will reduce the life of the bearings much more than if we were running a proper turbo setup from the factory (Lower compressor RPM on a daily basis AND when in boost, even at 20+ PSI). The 62mm turbo's Shiv is using in the single are used on 4 cylinder 2.0L's all over the place, and we have a 3.0 I6. Do you see my point?

The boost we run is within the compressor's efficiency range. Even though increasing the boost puts alot more stress and heat on the shaft and bearings (Not to mentioon the backpressure we face), we shouldn't be dealing with these issues. I have 19k miles on my car and am experiencing this, and I have never run more than 13.5-14PSI.

[A418t81]

Originally Posted by atomos319

Well, I get whine even when on map 0...1-2 lbs of boost, likely below stock spin speeds. And you noted above 4 PSI it goes away... not sure of the relationship between PSI and how fast they are spinning, but just because I make 21 PSI midrange, why would they scream under much lower boost? BTW the pitch of the siren goes up the faster they spin until I can't hear it.... usually above 3500.

I meant if you got new turbos and kept them below around 12-13 psi, they would most likely not develop bearing noise.

Your turbos have bearing noise now, no amount of low boost pressure will reverse that. Yes, they will make some noise at low boost and low rpm because that's where they aren't spinning all that relatively quickly allowing the noise to be heard. They scream down there because you've now run high enough boost pressure (21 psi in the midrange tapering to basically whatever the turbos can support) to cause the bearing a small amount of uneven bearing wear which leads to the noise that we hear at lower shaft speeds (lower boost pressure). Yes, the noise will go away as rpm or boost pressure climbs because your shaft speed increases and the noise become inaudible.


E90company, I apologize, I misread your post. I agree with you.

[Ilma]

Originally Posted by atomos319

Anyways, I brought it to them for an opinion. The foreman agreed something is definately "going on" with them, and reminded me that I have a two year warranty on the parts. With that in mind, he said that if they are performing, and not blowing smoke, I might wait until it gets worse before taking everything off the car and going back to the installing dealer.

This is your best course of action because you are becoming far too paranoid about a noise that many people have been experiencing without grenading the turbos.

As A418t already mentioned.....it's probably a little bit of bearing wear that does not impair the performance of your turbos.

Unless the noise becomes loud and constant all the time......or you start blowing smoke out the tailpipe, do yourself a favour and just accept it.

I was in the same boat as you three years ago when they replaced my first set of turbos.

The replacements have been sirening at low rpm spool since I got them.

They boost just fine and they don't blow smoke.

In fact you have far more to worry about from wastegate wear and rattle than anything else.

[daMau]

Sounds fairly normal to me, except that perhaps the whine hangs on a little longer/louder than I'm used to.

For comparison, here are some other 335i vids on YouTube.

Here are some other YouTube videos exhibiting the same noise yours does:
-

(video specifically directs the viewer to enjoy the sounds)
-

Here is my car on a dyno last weekend:

[KaiserN54]

a418 and everyone else who has chimed in- thank you educating me. feeling a lot less worried about things as a result. I will just roll with them and not worry about it then.

[Ilma]

Originally Posted by atomos319

a418 and everyone else who has chimed in- thank you educating me. feeling a lot less worried about things as a result. I will just roll with them and not worry about it then.

Good for you

I found a lot more peace of mind when I accepted the siren noise as being within the "normal" range.....and the fact that about half the people on this forum report experiencing the same noise. There is some comfort in knowing that it is not a defect particular to your car only.

Just so you know, over the last three years it has not gotten any worse. I do notice a bit more of it in the winter when it's really cold, but once the engine warms up it's back to the usual levels.

[E90Company]

Originally Posted by Ilma

Good for you

I found a lot more peace of mind when I accepted the siren noise as being within the "normal" range.....and the fact that about half the people on this forum report experiencing the same noise. There is some comfort in knowing that it is not a defect particular to your car only.

Just so you know, over the last three years it has not gotten any worse. I do notice a bit more of it in the winter when it's really cold, but once the engine warms up it's back to the usual levels.

This is good to hear

[zeenon53]

I just installed an intake and FMIC 2 weeks ago and catless DP's this past week. I can tell you that once I put my intake on I heard the turbo's whistling a good bit, as soon as I put the DP's on it was even louder. Mine sounds just like yours and i'v been tuned for maybe 50 miles now with 24k on the car.

[E90Company]

Originally Posted by zeenon53

I just installed an intake and FMIC 2 weeks ago and catless DP's this past week. I can tell you that once I put my intake on I heard the turbo's whistling a good bit, as soon as I put the DP's on it was even louder. Mine sounds just like yours and i'v been tuned for maybe 50 miles now with 24k on the car.

You are getting the siren type noise? (bearing)

[zeenon53]

Originally Posted by E90Company

You are getting the siren type noise? (bearing)

You know what, I was just listening to the videos again. I can hear 2 sounds, the turbo sound that everyone has and hears, then, listen closely, almost behind the turbo sound is a siren. I can hear it in the second video better because you don't hear the turbo whistle. I bet it is even more prevalent in person. I am not getting the siren noise.