I have my dp bolted onto the turbine housing, but I'm not sure if one of the nuts is tight enough. It's the one right under the bend, I can get a pic if needed, and it's a bitch. I think it's tight, but if I shine a flash light inside the housing, right at the seam between the dp and the housing I can see some faint light.

I can only see it in a pitch black room. It is very faint and can only be seen it the light is held on the seam. My question is, will thermal expansion fill this gap? I would think it will, but this is my first install and don't want to have to take the whole thing apart if it leaks. Thanks.

 

If it's small enough, the carbon buildup would probably seal it. Otherwise, you can maybe try running a stud/nut on that hole. For extra sealing, you could get one of these:

 

If your others are tight it will be fine. I run 3 bolts on my 5 bolt. It leaked for about 50 miles. Carbon sealed it up. No leaks at all with 2 bolts missing.

Run it, if it leaks bad Id sujest buying a gasket and let carbon do the rest.

 

I figure between thermal expansion and carbon build up it will seal, just wanted to make sure. The other 4 nuts are on tight. Thanks!

It is a stud/nut on the hole, just the dp is so close. It was perfect before I got it coated, but I didn't think about it when I had it coated. The coating is thick enough that it makes the nut a bitch to turn. I tried grinding it off, but was only able to do so much.