catalityc converter

[rjh41388]

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.

[Classicrocjunkie]

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"...

[-Jayson-]

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.

[Mangoamerican]

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

[Sunbird_Owner]

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

[Classicrocjunkie]

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.

[Sunbird_Owner]

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

[Classicrocjunkie]

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

[lexxxx]

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

[noshun]

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!!!

[lexxxx]

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

[noshun]

Originally Posted by lexxxx

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!!!!

[Sunbird_Owner]

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

[xxchamp34xx]

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

[bigdaveangell]

Originally Posted by Sunbird_Owner

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