This may sound like a noob question to some of you but....

I want to try and squeeze a little more horsepower and try to bring my spool times down. One of the suggestions was to gut out the catalytic converter. My car is OBD 2 and there is a sensor in the cat just after it.

What kind of consequences am I looking at if I gut the cat out? Will I throw a CEL? If yes, How can I run with no cat and not throw CEL's

Thanks

Jon

 

bump.......

Jon

 

I'm not obd-2 so I'm not positive, but I believe you can get an o2 eliminator that will make it seem like everything is ok. For some reason I think people just have the secondary o2's hang in the cabin too, I'm like 40% sure on this, so don't try it unless someone confirms it, LOL. It tricks it into reading clean air? Someone chime in, I'm obd-0 and don't know

 

Here we are:

http://www.o2simulator.com/

 

Some people have success in wrapping the tip area of the O2 with tin foil sealing it off from sensing the surrounding air.

O2's work by 'detecting' the difference in O2 molecules between what is in the exhaust gas and whats in the surrounding air ( Nernst Cell ).

So if you cut off the air, kinda looks like a rich condtion, yeah? And since catalytic converters USE O2 to do its job, when the converter is in place, the 2nd O2 should be showing a rich signal as the O2 is being used up by the converter.

Sometimes it works, sometimes it doesn't. On a decel condition, the 2nd O2 should def be showing a dead lean signal as the ECU has cut off the injectors....but the tin-foil method doesn't take that into account.

 

Actually the rear o2 doesnt show a rich signal all the time, its signal should be significaly less than the front, in the .3-.4 range on most imports, but should still cycle a little with the front o2. A good simulator will take the front o2 signal into account and send a cyling signal for the rear, just with less range than the front.

 

.3 - .4 is lean....the rear O2 is usually hanging around .6 - .8, and yes, there is a littel swing. But if the rear O2 actually tracked the front, it would be a sign of catalytic converter failure.