I am fixin to put a B18B1 in my hatch. what size exhaust do i need 2 run?

 

N/A or FI?

 

You could run stock exhaust if you wanted to. What are you planning on doing? turbo?
2 1/2 would be good..

 

When i did my swap i used the stock one from my 93 civic.

 

Any aftermarket, like Tanabe Apex Greddy Skunk, should be good. My B18B has a Tanabe SHMedallion hooked to it and it is good. But like the other cat said stock would actually be good too, until you do cams and pistons.