Alright here's the deal. I have a b18 swapped in my ek. Well I have a 2.5 in header outlet and a 2 and a quarter exhaust inlet. Currently I have th stock cat jimmy rigged on and i'm having all sorts of problems (exhaust rattles under the car despite the hangers, an exhaust leak, and loss of hp). Well my o2 sensor is in the cat , and the cat i'm looking at doesn't have a spot allotted for it. Before I order the new cat I need to know what/how/where will the o2 sensor go in the new cat ...is there a way ? I'm clue less with this honda tech please help

 

the o2 sensor in the cat is just to see if the cat is working. u should have an o2 sensor before the cat. that's your primary o2 sensor. the one your ecu looks for to correct afr. if you're running an obd1 ecu then it's not even looking for that 2nd o2 sensor so don't bother with it. if you're using the o2 in the cat as your primary o2 then you're gonna have some issues. hope that helps you.

 

its obd2 converted to obd1 ...will that have an affect on anything ?

 

obd1 won't look for the 2nd o2 sensor. 2nd o2 sensor is just to verify that the cat is working. you'll be fine as long as u have a primary o2 sensor installed before the cat. ideally in the header.