Is there a gasket for it? When I put my car back together I used RTV on it and I suck at RTV. I get a lot of whistling and I think that's where its from. Sometimes it sounds like a fire squad rolling through.
There is a gasket for it. I'm not sure you can buy it seperately, but you may be able to. I just purchase the turbo gasket set for an 88 TC, and it's in there. I used to get a really bad whistle, and it turned out to be the gasket between the turbo and manifold. Sounded like a police siren. Sucks changing them though.
I might have one laying around somewhere let me take a look. if I find it you can have it.
I have the really thick stainless gasket between the Turbo and Mani. I'm gonna snug everything down when I get a chance though.
The gasket to use is a nissian 300zx TT gasket, dont have the part number handy but it is solid copper and works much better than the factory gaskets. Not 100% it owrks with an IHI but I know it works with a T3 on the hot side.
The inlet side I've used cork before with pretty good success, its almost always under vaccum so it works pretty good.
The 300zx gasket you are talking about is basically what I have except mine is stainless steel. Really think and durable feeling.
I got the "turbocharger gasket" kit from advance from felpro. It has a few assorted gaskets, oil return, manifold , etc plus the inlet gasket I was looking for. Quieted it down a bit but still some noise. Ill try wrenching on the bolts sometime when its not death outside.
Might be worth checking the E6 for cracks too, I had a mani that would whistle until it was nice and hot and the crack sealed up some.