I have a 99 civic dx and i am eventually gonna do a b18c1 turbo swap in the next year to it, but i want to put a good exhaust in it now. If i put an aftermarket exhaust in now will all i have to do for my new enging to be switch to new headers? And what is a good/inexpensive full exhaust? Thanks!

 

No, it'll be **** face loud. do the 2.5-3" custom exhaust AFTER you get the turbo and engine put together.
What if your plans dont follow through? What if there's a complication? You're going to have an annoyingly loud Civic.

But to answer your question, yes all you'll need essentially is the exhaust manifold/header. Is it a good idea? nope