I have an 01 Civic DX and want to make a custom exhaust with a high flow cat and a nice muffler.
I was wondering whats the stock exhaust size on my car and if I should get bigger piping. I plan to spend some money on this car and possibly get a turbo. Thanks for the help

 

What's wrong with this?

 

I dont have enough dough for that. I just wanna choose what I put on the car like the style of muffler and custom cat.