question is, I hope to get a 6th gen 4cyl, and would like to take the cat off, It really helped my 91 hatch, and am wondering if there is a downstream O2 sensor and if I need anything to simulate the cat being there.....a lot of Grand Prix guys put O2 simulators into the downstream cat to give it the correct reading as if a cat was there.

Anyone done this?

 

I dont have a cat, and their is a second o2 sensor, a local exhaust guy made me a o2 cheater, you can also buy them online

 

No cat.

Redid my DP so the o2 sensor sits in the pipe along with an extra bung for wideband o2, flomaster resonator to "simulate" the look of a cat

 

I do the same thing on my S. The anit-foulers from Kragen work great to fool the o2 sensor.

 

get a high flow cat for $60 or less... (it's just a pipe w/ a hole to put the O2 sensor) look it up on ebay.

 

I would recommend a catalytic converter. It doesn't decrease performance, and it helps out the air you breathe.


I just talked to a mechanic who owns several shops, and he gave me a lecture on how he recommends one to everybody.

 

You make it sound like it's an option! 95% of the people not using one usually have a legit reason. You don't see people complaining about Nascar, Indy, etc. when they produce a heck of a lot more greenhouses gases than a regular car without a cat. Have you seen diesel semi-truck racing on TV? It's literally a cloud of black smoke coming out of the stacks.

 

Cars have been coming with cats for what...the past 30 some years? It only becomes an option when people remove them for performance reasons.

 

you may want to rethink that theory, imagine having a bunch of screens and such in your intake and tell me it doesnt restrict air flow

 

take it out... where I live is illegal, but, heck w/ it... mine is comming off this weekend... ($250 fine if get caught)