I need a little help on this one…

I was considering buying a hi-flow cat for my FD and I was just wondering if I would still be emissions legal (in Colorado) with dp, hi-flow cat, and cat-back? Also could I remove the air pump later with the hi-flow or would I need to leave it on?

 

I would think you would be hard pressed passing an emissions test anywhere without an air pump.

The idea is genius, pump in clean air with your exhaust.

 

You might try posting in the "Mountain section" of the regional forums for someone with experience, but I wouldn't think a Hi-flow with the pump would be any worse for emissions than the stock cat. Without the pump you risk plugging your cat prematurely anyway. Search here on removing the pump for more info.