I'm doing a custom exhaust (stacks). I plan on in the future making around 500 rwhp +/-. Now my question is, if I buy a 4" downpipe from DTR will it fit on an aftermarket turbo ? Are the flanges the same, or will I have to purchase another one once I get to the point where I need another turbo?

 

The 4in down pipe for the stock turbo is not the same most of the aftermarket turbos I have seen run a HX-40 stile or a 5in v-ban clamp.