I have a 92 Civic CX with a B16 Swap and 2.5 Exhaust. I need to replace my Cat due to poor fitment. While I am replacing the Cat, I am installing an ITR Replica Header.

My question is what length cat should I get? I've heard 12 Inches because of how long the ITR Header is, and I've also heard 17 Inches. Which size should I go with?

Thanks.

 

Bump

 

Huhmm???

2.5" piping + itr header???
Its just a comment from my personal experience, but I think this setup will work better in a 1.8L or stock 2.0L setup
2.5" piping its a little too big for 1.6L and ITR headers alone lower your mid range torque, and a B16 lacks of torque.
My advice would be for you to change to tri-y small tube and 2.25" piping with a WS2 muffler

But then again its just comment

 

just get an adjustable test pipe

 

I hear what you are saying, but I bought the ITR Replica for my B20VTEC I am building.

Since I have an exhaust leak from the Cat, I figure to go ahead and put on the ITR Header. I have to get a 2.5 Cat anyways, might as well go ahead and get the Exhaust setup for the B20VTec that way when I drop the motor in I'm not letting the car sit around waiting for a tune because I don't have it setup yet.

 

all makes sense nowadjustable one then

 

Install the header, then measure the distance between the header flange and your exhaust system.