im getting an exhaust soon (probably apexi ws bc its low profile) and i want to gut my cat. my friend with a 95 gsr, greddo evo cat back, gutted his with no problem. i have heard that gutting a cat on a car with an obd II can cause a check engine light to come on, is this true? anyway around it? how much for an all new cat and is it worth it?
thanks

 

anyone? i know its a gay title, that doesnt mean you cant help me though

 

if you gut your cat you SHOULD get a check engine light..... i wouldn't waste my tine gutting it.. i doubt it will make enough differance to warrent driving around with a cel on... you can buy a simulator for the second O2 sensor although i dont know how reliable they are.... or you can go obd 1 i plan on doing that in the not so far future..

 

OBD II cars have a second O2 sensor mounted in the cat that measures how effective the cat is working. If you gut it, the OBD system will think your cat has failed and will throw a check engine light telling you to fix it. It may also put you into limp mode where the engine pulls some timing and adds fuel to protect itself till the problem is fixed and the code goes away. Modern cats are very efficent. There is almost no power to be gained by gutting yours.

 

yeah if you really want high flow. just get a high flow cat

 

yup. Theres really no difference between a modern high-flow cat and a test pipe in terms of flow... a gutted cat would probably cause more exhaust turbulence than either of these.

 

alright, thanks for the tips guys

 

First of all it's ILLEGAL to do that. According to the goverment you have to run with all emissions equipment in working condition. PLUS PA might install new emissions stations next year anyway.

Be responsible and run with a catalytic converter. I hate it when I'm behind people with smoking tailpipes when I'm driving with my windows down.

 

ok, no power gains+check engine light+possibly illegal=dont do it
sounds good to me :fawk:

 

Let me tell ya a very true story.

Once upon a time, Ricer boy guts his cat and welds back in place. A month later Ricer boy gets in an accident with a family hauler and a little kid gets a little hurt. Further investigation is called for on Ricer boys car since some items look questionably legal- tail lights, head lamps, more than two fog lamp assemblies, etc. The investigating authorities find Ricer boys' cat gutted (DOH!) and I don't mean his pet. Ricer boy is not only found at fault in the accident but is slapped with a $10,000 fine and 1 month in jail for violating California Air Pollution Control Laws and the Federal Clean Air Act. Ricer boy now walks or takes a bus and will for the next year due to licens suspension. The End.

Sad story eh? Don't be like Ricer boy, buy a high flow cat.