I forget all the scenarios...what fits and what needs to be changed...

I'm putting a 1.7L in my project 914
will my 2.0L heat exchangers work?
I have a crazy VW aftermarket exhaust and a 2.0 hanger...

Yes. Exchangers, exhaust and hanger must match.

I started a post and did some searching about the difference. There are a couple pictures that help explain the diff and what goes with what.

http://www.914world.com/bbs2/index.php?s=&...t&p=2131214