has anyone here gutted there cats or ran strait pipes?

in all my cars i always eliminate the cats, but i never had a car that had a 02 after the cat. Would it effect the 02?

 

I bet it could affect things. I've got no cats, but also no 02 sensor afterwards.

I'm sure there are ways around it, though. The later Supra TT boys run an 02 simulator to feed the ECU. Do a search on Supraforums, its not too difficult. You could also probably just run the leads from the rear 02 sensor in parallel with the main 02 sensors up front. That will at least give the ecu something to think about instead of a 0 volt signal.

 

The second O2 sensor verifies that the cat is working. It's looking for a constant signal (like .12v) with little variance. A hollowed out cat will set a code, but so will an exhaust leak before the cat anywhere. If it works, that simulator thing sounds like the only way around the stock ECM.