i have a 98 sunfire with a 2.2. I'd like to remove the catalityc converter, but I dont want to mess up my engine. I think something on the engine has to be tuned when the backpressure is changed, but Im not sure. Does anyone know if that has to be done, and how.

well there is 2 things i can tell you here...

Depending on where you live you need a cat to pass emissions inspections. Replacing it with a high flow cat will help you out with better air flow. Also remember now with removing a cat there is a chance the mixture that was fired won't have been fully combusted and eventually clog your 2nd O2 sensor throwing a code and messing alot of stuff up. You also need 2 O2 sensors to funcion properly. Now if you are in a state where you can get away with no CAT you will need this http://rksport.com/product/p_02094035/view_detail to bypass the 2nd O2 sensor... Also to maintain back pressure you need to not be over piping of 2.5"...

and you dont need to tune the engine really, just make sure all your o2 sensors are their and you should be fine. A high flow cat really wont add much noticeable power alone.

i saw a 02 sensor replicator at autozone.. so if you wanna go that route

Alright... just curiouse... Got a 94 sunbird... do I have to get one of those too if I rip the cat out?

if you have an O2 sensor after the cat then you do... but if you only have 1 in the header then you don't.

Do I have to keep the piping the same size too? 2.5? I wanna do this it would be a quick way for me to gain some HP because it is not illigal to not have them out here. Also My cat is just bolted in. THanks

It would be a good idea that you keep the same diameter all the way back....

i have one o2 sensor on the deaders i just unscrewd the cat then welded the same size pipe in its place got a good power increase

I wouldn't let too many people know about your cat replacemnet if it should be there. You don't want a ticket. I high-flow item is a little dearer but you can pick-up a Magnaflow high-flow cat for $100 from nopi. this being your best bet. The simulator makes you check engine light come on so you'll ignore it and if anything does go awry you won't know!!!

well for 3 bucks of metal i got a high flow exhaust

well for 3 bucks of metal i got a high flow exhaust

For $10 CDN I got a heat shield and feed for my Vibrant Intake. It also reverberates in the sheild and the induction roar is amplified. I sound the shit!!!!

if you have an EGR valve is it true you have to plug it? I mean your gas milage would go way down with out a cat and that still opening

I knocked mine out and put a header intake and high flow magnaflow exhaust :) seems to be working just fine and sounds pretty damn good for a 2.2

if you have an EGR valve is it true you have to plug it? I mean your gas milage would go way down with out a cat and that still opening

You dont have to but if you dont you will have a big exhaust leak

Hi im new here and i would like to know if it's possible for me too to bypass my 2nd o2 sensor...?

I have an Accord 1996 with an h22 whit no catalyste and 2 1/5 line au exaust...

Tx for your reply.

:icon16:

Hi im new here and i would like to know if it's possible for me too to bypass my 2nd o2 sensor...?

I have an Accord 1996 with an h22 whit no catalyste and 2 1/5 line au exaust...

Tx for your reply.

:icon16:

You need an O2 sensor simulator!

You need an O2 sensor simulator!
Ok and where i can found thet you think

(sorry for my english i am a french canadian...:) )