what's the difference between a N/a cat back system to a turbo catback
 

I wanna buy a cat back system for my 87 N/A but implaning to make it turbo in the future . And i want to know if a turbo catback will fit a N/A engine or what shoul i do.

Thanks for your help and advices

The catback exhaust system will be capable of switching over. It doesnt matter.

the only one I know about is the Racing Beat system. The "y" pipe is the same for turbo & n/a, the mufflers are a little bigger & louder for the turbo (at least this is what Mazdatrix told me). I've got the turbo mufflers on my n/a, they're pretty quiet, only get loud when ya want 'em to...

The exhausts themselves shouldn't matter, you can fit a turbo on an NA, or an NA on a turbo. The only real difference is that the NA is louder than a turbo, so the mufflers muffle more. On the other hand, if you put a Turbo system on your NA, it will be loud as hell. Of course, you may like that :)