Ok i am swapping a b18b1 in my 91 civic hatch std. I was wondering if the stock exhaust will really hurt the power. I got a aftermarket header, but has a dent. And i let my car sit for bout a week, cuz i was working on the muffler, and i started it without the muffler i saw water shooting out and it looked like rust water is this bad?

 

Not really unless you planed on going boost!

 

ok thanks im going boost but not right now. So i dont wanna waste money on buying a exhaust then changing it for a bigger pipping, so im just gonna buy a 3" later

 

you will be fine...