As titled, response much appreciated.
thanks

I think the only real difference is hearing the turbo's spool up and then hearing the BOV. Other than that, you can't really tell. At Idle, it should sound the same for the most part.

Mine sounds quieter than an NA car with my same exhaust and it stays alittle quieter during full throttle. You can really hear the turbos when they spool up especially at 14+psi.

are all types of BOV audiable? Are there any "stealth" BOV?

Turbo'ed cars are generally quieter than equivalent non-turbo cars. The turbochargers act somewhat like mufflers by cutting out the exhaust sound.

As an example, I, for a very short time, ran my Z32TT with straight pipes (no cats and no mufflers) and it was still tolerable. Try that with a non-turbo car and you will blow your eardrums (figureatively)

However, with a turbo'ed car, you will hear the turbos spooling up, and if you have a BOV, you will hear that every time you let off the gas after being in boost. All things being equal, though, a turbo'ed car is more quiet than a non turbo car.

Dave

so a BOV is not a requirement for a turbo setup? And I assume there are BOV will different "volume" of sound too?

If you are going for a stealth look and still want the ability to release the compressor side pressure from your system some sort of bypass or BOV is necessary. It prevents compressor surge and can either be really loud and audible or damn near non existent. A recirculated BOV back into the system cuts down on sound dramatically, additionally using a bypass valve instead of a BOV will all but eliminate all sound made by the pressure release of the turbos. Think of a bypass valve like something on a stock turbocharged vehicle....you can't hear those turbos when you shift....same principal only applied to an aftermarket turbo system.

A turbo system itself will make you NA engine quieter throughout the RPM band. The very nature of running your exhaust gases through more piping (turbo exhaust housings) will reduce the volume of the exhaust. Certainly a lot depends on the exhaust set up you have, but regardlees the note should be quieter under all driving conditions.

i have no cats and at WOT MY **** SCREAMS

think the BOV is the only thing that tells you the dif.

Well, thats why. If you also had no turbos, it would be even louder. The turbos (as I said earlier) quiet it down some, kind of like mufflers, but don't make it silent.

Dave

it is quieter; sounds like a choochoo train, until the BOV goes off

thanks for the responses guys.

They turbos will make a whining noise too, it's farily subtle on all the cars I've heard though.

I had test pipes n/a and now have them turbo.. the car was loud as hell n/a, much quieter now but it still sounds mean at WOT.. I love it.