Turbo noise when spooling into boost

[e-jump]

[SOLVED] Turbo noise when spooling into boost [Boost Leak]

Hi folks
Need help on my turbo issue.
After reinstalling a rebuilt T28 (yep, i have the comp wheel fins shattered), i have high pitch noise whenever engine under load into boost.

It doesnt make noise on startup or drive under vacuum.
Theres a feel of little lag to full boost, but im not sure if its because of upgraded bigger comp wheel or due to this issue.
(I can only full boost on 3rd gear onwards. In the clip below, i did not push hard on 3rd and onwards, worrying issue might get worse)
Just checked the turbo, no shaft play.
Help,what could be the problem?

http://youtu.be/o8lppf8WUYw

Thanks

----edit; Feb 16 -----
Issue is due to boost leak from a bad clamp on IC hose.
Updated thread title

 

[4gbanger]

who rebuild your turbo? if the turbo becomes more lag than before, might be the comp wheel material is so heavy thus its making the turbo lag.

 

[peterj]

the last time i got weird sound from turbo and got lag is when the turbine clipe flew off and the turbine wheel keep scratching the housing and yet leaking exhaust till lag and cant boost up..just my experience may not be the core problem of yours...

 

[^pomen_GTR^]

bigger comp wheel sure will have a little more lag than stock...


but the sound doesnt sounds like usual whistle during boost build-up...

perhaps u need to check if there is any leak vaccum hose/turbo hose...

---------- Post added at 02:20 PM ---------- 6 hour anti-bump limit - Previous post was at 02:20 PM ----------

bigger comp wheel sure will have a little more lag than stock...


but the sound doesnt sounds like usual whistle during boost build-up...

perhaps u need to check if there is any leak vaccum hose/turbo hose...

 

[e-jump]

hi folks.
i also got few inputs from /o/ anons and they highly believe its boost leak rather than exhaust leak or turbo issue.
*I forgot to put the info here that i dismantled the whole IC piping n exhaust manifold to clean up metal shrapnel n get space clearance.

so far theres still no shaft play side2side n push-pull and no smoke.. comp wheel blades looks ok.
I had to wait till weekend for the workshop to open after cny holiday.
i already got inlet cover that can snug fit on the turbo comp inlet, just dont have strong air comp.

The turbo was rebuilt by speedspin, so i trust them.
It was originally a journal FRP T28, and got rebuilt with
- comp. and turbine house retained, shaft and turbine wheel retained.
- comp wheel upgraded to S15's because FRP repair kit discontinued(60 trim i believe? just bigger by 1-2mm), center bearing housing swapped to garrett T25's

 

[e-jump]

so today i got the issue fixed.
One of the IC hose clamp (under bumper) was a little loose.
indeed its boost leak.

I underestimated the air compressor pressure at ~20psi.
The plastic cap that i use to cover the turbo inlet flew lol.
Next time, i need to clamp it down like clamping the pod filter, hard :v

 

[vr2turbo]

What plastic cap on turbo inlet? Turbo inlet not link to you air filter hose?

 

[e-jump]

in order to pressurize your intake to find boost leak, you need to cap of your turbo inlet..
That means, off goes the intake pod/filter.
see below
2G Turbo DSM Boost Leaks -How to test and fix

I found a plastic cap of my hair-gel that fits nicely on the inlet. So i thought i can just cap it and hold there w/ hand. Didnt happen. High pressure pushed it out.
I should get a hose and clamp the cap to it. [Cap clamp to hose, hose clamp to turbo inlet].
I did not drill any hole on my cap as I use my turbo-to-ext.wastegate boost line instead for the air compressor input.
Drawback to my method, i wont be testing my WG for leaks under boost.

 

[vr2turbo]

Oh! for test purpose. Wondering what plastic cap......