[pearadiise]

A little back story:

I have a high mileage full bolt on E90 N54, well maintained and taken care of running an MHD Stage 2+ flash tune. The stock turbos, as far as I know, have been replaced a very, very long time ago. Boost feels great and experienced people say based on the feel of the car and the logs, the car runs great.

About two months back I was installing a VRSF intercooler and noticed what looked to be metal flakes in the pipe leading from the outlet to the intercooler. I kinda knew what it was and expected it.

Fast forward to just this weekend, about 12 hours ago actually, me and a buddy of mine who owns a private shop decide to install VRSF inlets. The turbos based on the exhaust side looks great with very minimal shaft play, like not really even noticeable. The other side, better known as the compressor or inlet side can only be inspected after the stock inlet is off.

Unfortunately, after taking the rear inlet off, both of us witnessed a little bit of a worrying sight. Most of the fins or blades from the compressor wheel were chipped at the corners. I included a picture for better understanding.
I'm going to be going for an upgrade soon after seeing this, but I just want to know what could've gone wrong to cause this damage. Also, is running the car with upgraded inlets in the condition it's in going to hurt it even more or am I safe to continue?

All leaks have been taken care of in the past and oil changed at correct intervals. I haven't noticed any heat soak issues either. The car had to have had this problem for some time now, but the responsiveness of the turbos are great and they hit peak boost no problem, but maybe I don't know what I'm talking about or I could just be pushing them too hard.

TLDR; Doing inlets on my stock turbo FBO N54, noticed chipped/damaged rear turbo compressor. Can anyone help me figure out what could've caused it? Is it safe to run with upgraded inlets for a little? I will be swapping out the turbos in the future.

Edit: I also rarely push my car hard. I'd say like maybe maxing it out on the highway like once or twice a week and I drive probably around 220 miles a week. One out of every 6 or 7 pulls, I'll throw a 30FF after the boost tapers down at about 6k RPM. All my lines have been replaced and the wastegates aren't in bad condition. I'm assuming my problem with my rear turbo could be causing the occasional 30FF.

[Emilime75]

Something(debris) possibly made it's way into the intake and made contact with the blades.

With that said, I'm going to call you on some things. You can't come in here and tell us how amazingly well kept this car is maintained and how incredibly well it runs, then show a photo of oil leaks and tell us about your 30ff problem.

[Cm452]

Is there corresponding damage to the compressor housing? I ask because it's possible that the wheel was damaged during previous service/ rebuild. However, I'd also sus out wtf could have entered the intake and how. I wouldn't run the car at all with the turbo in that condition. A turbo like this likely has severe internal damage, and the accompanying imbalance is a time bomb. On the other hand, they've lasted this long, so maybe you'll continue to get lucky.
-Cm

[pearadiise]

Originally Posted by Emilime75

Something(debris) possibly made it's way into the intake and made contact with the blades.

With that said, I'm going to call you on some things. You can't come in here and tell us how amazingly well kept this car is maintained and how incredibly well it runs, then show a photo of oil leaks and tell us about your 30ff problem.

Fair enough and that's what I was thinking. Maybe in the past, something got lost or stuck in the stock inlets and made its way to the rear turbo and chipped it.
As for the oil leaks, everything from valve cover gasket, oil filter gasket, rear main seal, have all been done before any mods. At the time of installing the inlets and even way back when I was installing the intercooler, there were no additional leaks. Understandably it's very sloppy to just leave the residue there.
and blowing a 30FF once every 6 to 8 weeks doesn't mean my car isn't well maintained. It builds boost fine and the engine doesn't seem to struggle.
Everything that goes on the car (besides turbos obviously) has been replaced by me. Injectors, sensors, vacuum lines, spark plugs at every 10k, oil at every 4k, etc.
Not sure about how the last owner(s) took care of the car considering I've had to put a lot of time and money into it after buying it.

[pearadiise]

Originally Posted by Cm452

Is there corresponding damage to the compressor housing? I ask because it's possible that the wheel was damaged during previous service/ rebuild. However, I'd also sus out wtf could have entered the intake and how. I wouldn't run the car at all with the turbo in that condition. A turbo like this likely has severe internal damage, and the accompanying imbalance is a time bomb. On the other hand, they've lasted this long, so maybe you'll continue to get lucky.
-Cm

From what I can see, there isn't any other damage besides the compressor itself. No scratches inside of the housing and the exhaust turbine seem to be in perfect condition with just about no shaft play.
The other turbo is safe and looks untouched by anything that could've entered the intakes/inlets.
I noticed small metal flakes in the intercooler (outlet side, not chargepipe side) months ago, so the damage had to have been done a while ago. Who knows when though.
I'll probably baby the car until I can get the time to get new or upgraded turbos.
Problem is, I've made the dumb decision to have that as my only car and daily driver. I might pick up a beater car soon since I got a new job that I start next week and I can't really afford to not show up because of a problem like this.