Guys just finished fitting my MD321T to my 2003 sti, all went well ran upto temp, no signs of oil or coolant leaks on the unit so all good, Well took it for a little run, nice and easy till I get it remapped. Drove it about a mile parked up let it idle for a little turned the engine off and there is a very low pitched whistle from the turbo whch lasts for a good 5 seconds and slowly faintly disappears, is this common with the MD series?
Thanks Dean.

 

i wouldnt be taking it onto boost without a remap mate

as for the sound, i'm not sure..

 

Yeah I'm not booting it about just took it out to get upto temp to make sure everything is leak free.

 

Its just the turbine spinning down after the engine has stopped, nowt to worry about.

 

mine never did that

 

I thought so mate, but doesnt the lack of oil pressure when engine off premeturely wear the bearing?
Does the turbo hold oil in it's housing during that period?
Sorry for all the questions just don't want it going bang.

 

Its the blade spinning.

& for both you questions, no.

 

My old vf28 did it, my s206 does it a bit but I can't hear it unless I've got the bonnet open.

 

Probably get slated for this by the DV police but yes I have HKS SSQV fitted, the noise is clearly the turbine/bearing spinning down once the engine is off, just want to know if other users have noticed this and hopefully nothing to be worried about.

 

My 321t also does this, my Subaru mechanic whom I completely trust has told me it is nothing to be concerned about.

 

nothing to worry about.

 

Thanks for the comments guys, guess i'm worrying about nothing then.

 

All ball bearing turbos do it.

 

my sc46 when turned off from idle spinns for about 20+ seconds

 

what you doing with your old turbo dean?

 

My VF28 did the same.

 

I know exactly how you feel. Installed a new forged 2.1 with second hand MD321T and mine did exactly the same. Thought I could have bought a duff turbo but had a running in map by Simon (aka Jolly Green Monster) today and he put my mind at rest. As said above it is just because it's a roller bearing turbo and it spins down when you turn the car off.

 

yep totally normal as said etc

Simon

 

Love that sound

Banny

 

Yep me too, it's like a fighter jet winding down

 

Never noticed it with my 321H!

JohnD