Custom turbo manifold and oil return

[lahondal 17]

Hi all. 

 

I have one big question and one smaller doubt. 

 

First is if would be beneficial to cut the exhaust manifold flange to allow it to expand. 

Its just milled as i have it previously distorted, not sure because. At some point i have used the wrong nuts and became loose, probably when hot, and the other option is the flange is causing tensions that cause the manifold to bend. 

 

The big doubt is to cut or not the flange (as photo) , to allow the manifold expand slightly with heat and avoid bending. Seems a common practise in US when leak problems appear. What do you think? 

 

Second pic is the turbo oil return. Because manifold design i must to have the turbo center tilted, about 20 degrees or so, and i have had some smoking problems in the past (not sure because turbo seals or dodgy oil return).

 

I want to ditch the idle smoke one for all, and althought the new turbo is a BB turbo and oil flow will be less than before, id like to know whats your opinion about this return line. ID its about 10mm in the "bendable" inox pipe. 

 

Thanks all the replies. 

[Tom Fenton 1,542]

10mm oil return is way too small. Aim for 16mm+

 

I would not personally cut the head flange.