Hey, been a fan for like a year now of the site, and I finally got the money to build my turbo. Well I went and bought a turbo, pulled it off a volvo, td04h. I was looking at the compressor housing, and there seems to be some type of blow off valve maybe attatched to it. Does anyone know what that is, Ive searched around and everyone says its some vacuum housing, but i dont think it can be because of how its located. Ive heard of compressor bypass valve... could that be it, and if it is, do I need a bov now, and will I still get a decent sounding swoosh, granted I know the swoosh is over played, and some dont like it, it gives me chills hearing it. thanks

 

ok, if it is a disk looking part with a rod coming out of one side, then it is the wastegate. It should be connected to the compressor housing on one side and the rod to the exhaust housing.

 

does it look like this?



if so, yup, i think it's a bypass valve and i think you won't hear anything like a BOV when it does activate...

HTH

 

Volvo used a built in blow off valve on the turbo for a short time, the customers complaned about the sound so they stopped using it. If you have one of these you dont need a BOV, lucky you. Now the bad news, the Volvo mounting flange is a freak, they were the only ones to use it, you will need an adapter plate to use this turbo on a standard T3 manifold. If you are using a HF manifold its no big deal as you are going to have to make an adapter anyway, just take it to a machine shop and have the raised center portion turned on a laith.

 

cool thanks everyone for your help