New turbo, weird noise?

[EatingInternet]

So long story short I used to have a 05 legacy gt that got stolen about a month and a half ago, and replaced it with another 05 but wagon this time. On the drive home from buying the wagon, the turbo blew (130 mile drive). There was excessive oil in the inlet and tb hose, and it had front and back shaft play (but almost no side to side. Clogged filter yada yada yada been there done that, last car had the same problem. Replace turbo, remove filters, etc.

 

I decided to replace the turbo with an amazon unit with a billet wheel in the interest of time, and because I didn't trust the $140 stock rebuilt ones, nor did I want to pay $600 for another stock from rockauto. We can argue about this decision all day long but it's on the car and it works. Builds boost great.

 

However, I'm getting a really loud turbo spool noise and blowoff valve sound right around 2500rpm to 3500rpm. This sounds like whirring wind or like an open turbo that has no air filter or inlet tube and when I let off the throttle it whooses like I almost have a real BOV, but I have all stock recirc valve, intercooler, etc and this car did NOT make this noise with the last turbo. Similarly, my last car with a BNR evo3 16g also did NOT make this noise and that was with uppipe downpipe and other stage 2 mods. It's important to note that under full throttle above 4k rpm the car sounds perfectly normal, it's only just as its building boost it makes the noise. The best description for this noise is honestly like Cleetus McFarland's Leroy as the turbos spool up or down.

 

I find it hard to believe the car suddenly made a new boost leak as nothing leaked before I swapped the turbo. I double checked both ends of the TB hose and they were fine. The inlet clamp is also tight. Gasket on the intercooler appears to be in good condition. What gives?

 

My ideas:

-Boost leak (intercooler, the hose "T" next to the turbo with the restrictor, elsewhere?)

-Exhaust leak (I did have to use a shitty gasket on the lower downpipe gasket since I didn't have time to drive out and get an MLS one, but I don't hear any exhaust leaks at idle, maybe a leak at the uppipe or downpipe? I used Mahle MLS for those.)

-Turbo/billet wheel just noisy? No mechanical problems just different

-Something related to me rotating the v-band on the turbo as it was in the way in the coolant bolts

-???

[Max Capacity]

Did someone remove the intake silencer under the air filter box ?

[EatingInternet]

I did change the air filter and had to wiggle the box around a bit. Maybe I accidentally disconnected it? I'll check this weekend when I see the car again, thanks for the input.

[RecklessWOT]

I intentionally had that completely removed from my stock intake for the longest time (I know that's an unpopular opinion around these parts I don't need to hear it, not running the stock intake anymore anyway) and it made little to no difference in sound. Made a slight deep growl under acceleration, but absolutely no difference in turbo spool or recirc noises.

 

Are you sure the cover is properly seated on the airbox after the filter change? If not, that would cause it to make more noise.

Edited November 10, 2019 by RecklessWOT