This is doable with no detrimental effects, right? The reason I ask is I wish to change the exhaust on my 91 NA, but later on down the road I'm looking to drop in a turbo.

 

The turbines soak up a lot of noise, so "turbo" exhausts are usually designed with less noise attenuation capabilities. Also, depending on the horsepower levels, turbo exhausts tend to have larger diameter piping. In most cases, using a turbo exhaust on a non-turbo engine will yield more noise and less horsepower, but I am not aware of any other detrimental effects.

Additionally, the downpipe design is usually different between turbo and NA exhaust systems, so the NA downpipe off the header may not fit to the turbo exhaust without modifications. Also, turbo outlets and mounting locations are not universal, so the type of turbo and manifold you eventually choose will also require its own unique downpipe.

Unless the current exhaust on your NA is worn out, I would recommend waiting until later and installing a turbo exhaust after you install the turbo engine.

 

A catback for an NA will work on a turbo car unless you want a full 3" system. The rest of the exhaust system is different. As stated, the turbo and NA downpipes are different.

Also, you can't "drop in a turbo." It involves a lot more work than just slapping on a turbo. Look in the 2nd gen technical FAQ for more details.

 

if you do do this get 3" way get a muffller with a diffuser so you can add some back pressure for you n/a or it will run a little slower

 

^ damn beat me to it..yea that pretty much covers it. get an exhaust for a na prob 2.5' tops..alot of people say they will drop in a turbo in the near future..chances are it will be a long time before that happens..even once you start the turbo project it will take a while interchanging/adding parts if not another t2 engine in your chassis.