_Endless_

i'm running a garrett t3/t4 on my b16 boosting just 6psi right now. i'm using a 38mm external wastegate and a greddy tvvc manual boost controller.

i had the boost controller hooked up to the side port of the wastegate and left the top port open. recently, i noticed that whenever i started the engine i could hear exhaust leak noise. it sounded like someone is running open header but not as loud...just noticeable.

i'm running open dump tube on the wastegate so i tried covering the tube with my hand to see if i could feel any hot exhaust but i didn't feel anything so i just thought maybe my exhaust has a hole on it.

yesterday, i re-routed my mbc as adviced by friends to tial's diagram ->http://www.tialsport.com/docum...l.pdf so i had to unhook the lines.

after re-routing the mbc, i started the car and the exhaust leak sound wasn't there anymore..maybe air trapped inside the lines got out when i unhook the lines. i tried driving the car around to test the new setup but it's overboosting to 10psi..probably the vent should be bigger than the 1mm i put in. after driving around and shutting down the engine, i restarted the engine and the exhaust leak sound is there again but a bit louder this time before it tapers off a bit.

is this normal or is there something wrong with my greddy mbc? anybody experienced this before?

White Smoke

The BC is not gonna cause that sound! Are you sure you installed the metal fire ring when you installed the WG? Are you running any kind of gasket where the WG mounts to the manifold?

_Endless_

yes i did install the fire ring. in fact i've been using the wastegate for several months already and it's only recently, like 3 weeks ago that i started to notice the sound. i'm also using the gasket that came with the wastegate.

i'm thinking that maybe the air that pushes against the wastegate spring during boost got nowhere to go after boosting(deceleration) hence the wastegate cant close fully.

i'm going to checking the bolt holding the wastegate to the manifold tomorrow and see if it got loose.

White Smoke

The exhaust gas does not reach the top area of the wg ever so it's highly unlikely thats it's leaking from there unless you have a faulty wg. My money is on the gasket, trash it and run w/o one.