Ok so I have my 2000 ss m6 and I'm wanting to know if I straight pipe my cats or go lt with catless y how many o2 sims do I need until I can afford my tune with other parts added in?? I only have to sim the rear correct the pre cat o2 just needs to stay in place??

 

Yes, only the two after-cat O2 sensors get replaced with sims.

 

Thank you injuneer I appreciate the info

 

So where can you get a sim?
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Probably on ebay. Casper Electronics used to sell them, but the EPA got after them, fined them $70,000 and forced them to stop production. Technically, they are illegal, because they defeat required emissions systems.