nbressette

Recently my car has been making more and more spool noise, I know I know, talk about a good problem to have. It started as one corner that at low speeds in second gear I could really hear the spool noise from the passenger side (mostly because it echoed off a retaining wall on my way home from work).

Now its progressed to the point where I can hear very noticeable spooling noise (or what sounds like spooling noise) as low as 2k RPM on the open road.

The car has what I've been told are stage 5 UMW ZC turbos and a militek exhaust w/ cats, headers, stock airbox, upgraded turbo hoses / intake tract, and 74MM IPD plenum. Its running a custom MAFless tune from Sam that yields 1.2bar.

The car still pulls like a freight train and beyond the excessive spool noise from what seems like the passenger side there are no other issues. It does smoke a little bit on startup if its been sitting for a while (what car doesn't?). I'm just wondering if this is indicative of an imminent failure of some kind or normal and it was previously not working normal. Going to pull it apart this weekend to see if any hoses came loose / do a pressure test. I also have a new set of DVs to swap in.

This video does a good job of capturing the noise, in person the spool noise is even more pronounced.

Atrox

Don't know what the problem is, but that sounds bad ***. Has boost gauge always read 0.0 under boost?

nbressette

I KNOW! Now I'm torn between dreading what could be broken and excited that its normal and just makes boost that easy.

Dock

Call Kevin at UMW and see what he thinks.

vogz

What intake setup on the car? I know you said MAFless, and that sounds like mine with filters on the turbos. If this is a new sound and you don't have filters on the turbos, then your intake piping pre-turbo could have come loose. You wouldn't even know since you have a MAFless tune.

Rvca3112

Check all hoses under the car and if possible check for boost leaks?

Third-Reef

Pull your turbo inlet tubing off the turbo, grab the little nut in the center of the compressor wheel and see how much it moves up and down, side to side. Should move a little bit if it moves much your turbo bearings are going out. Big increase in turbo noise can be a sign of bearing failure.

nbressette

Stock airbox.

nbressette

For sure, I'll check it this weekend when I do the pressure test. Very likely based off the miles (70k) and the small amount of smoke on startup that I'm at the end of the bearings life.

nbressette

Tried that, basically the options are to either rebuild them or don't. If a re-build is in my future then I'm move over to the tial guts from Sam.

SamboTT@ByDesign

Hey! A little bit is normal but if it got a little bit louder all of the sudden something is a little bit loose. Or has come open. My bet would be the inlet piping at one of the joints. Should be easy for you to look over it and you can always call me while you're in there. Another slight possibility would be something feeling inside the exhaust. Turbochargers should be perfectly fine. If it was them you would not be making boost or power.

Sveach756

N75 hose under the y of the intake pipe intact? I had this happen last year, the tubing just heat cycled and broke off.
Shawn

nbressette

Thanks, I'm guessing once i get the rear bumper off I'll be able to tell where its coming from. If I get stumped I'll give you a call.

Thanks for the tip. I replaced the N75 earlier this year and zip tied it but I'll check it out to be safe. When yours did it did you notice any other symptoms like power loss or low boost?

911mhawk

Do a pressure test and then a see what you you hear.
Maybe you have a leak, or your boost gauge is broken, or you just never really put your foot in it.
Or, take it to a shop that knows how to test for leaks then go from there.
Leaks are you first concern, any tuner will tell you that.

SamboTT@ByDesign

Cheers
My money is on the suction side so the pressure test might not find it. But always do one.