i was wondering if FD stock turbo supost make a high pitch sound when acc. from 1000rpm~4500rpm (primary only) ?
I mean, its loud enough that you can hear the turbo spooling from a block away. Im not even sure if its a stock twins or modified twins, since i bought it used 1-2yrs ago. (no mechanical problem with turbos)

so, is that nomal?

 

I'd say it depends on the mods the car has (not just im the turbos are modded). Mods like intake dp and upgraded boost definately will make the turbo louder, but I'm not sure loud enough to here around the block...

To give you an idea, after I added intake I was able to hear a hissing sound inside my car when the turbos spooled up.

GL
Jason

 

you should not beable to hear your turbos spool up a block away! even with a T51-kai, i doubt you could hear it a block away. perhpas something is scraping...

 

There is no way to here it a block away, but with a downpipe you can freak out your passanger when the boost comes on.

 

unless you got your crv venting to the atmophere. You will hear the secondary venting till you start using it. Mine is venting and its pretty loud vaccum cleaner.

 

Does it sound like a dentist drill when you get to about 0psi and up? If so it sounds like the thrust bearing is bad.

STEPHEN

 

SPOautos

yea my primary sounds like that "dentist drill" when the boost goes above 0.6mm^cm2.

and it literary sounds like a Bowing 747 Aircraft jet engine spooling up....lols (yes i work with passanger aircrafts)

 

Sounds like a bad thrust bearing then.....rebuild time

You can check it by pulling the intake pipes off and seeing how much play is in the compressor wheel. Just nudge it from side to side and front to back. You should only have a small amount of play side to side (like a 1mm) and you shouldnt have ANY play front to back.

STEPHEN

 

Yeah, the fins on the compressor wheels will start touching the housing and make that sound. I had that sound once when a mechanic tried to weld a crack in my housing and pass it off as a new one that I paid him for. The tolerances are very close so the fins were touching the weld seam. Not good on the car but kinda sounds cool.

 

I wouldn't want little pieces of metal going into my engine, but that's just me.

 

Well, two different times I had that same type of loud vaccum like spooling noice. The first time was when my intercooler piping came loose when I was driving and afer tightening it the noise went away. The second time was when a shop that put my charge pipe back on for me, put the vaccum lines on wrong so it was making that loud spool up noise just like you described. I'm guessing you made sure your intercooler piping is fine, so I would get a expert to make sure that your lines are correct. It worked for me.

 

I know its not the intercooler piping because I have just replaced them with greddy and it's doing the same as before. As for the lines, im not sure...so i guess i'll check that out.

thankx

but yes, it does sounds sOOOO good!!

 

just pull the intake and check for play in the compressor wheel. That will tell you if the turbos are good or not