Whats the smallest, most free flowing catalytic converter I can get? I've seen one on ebay thats like a replica of the Dynatech Powercat hi-flow converters...but r they more high-flowing than the Magnaflow's?

 

Hard to tell what would flow the best, every company says theres does. I use Magnaflow 3 inch universals and they don't seem to rob much power.

 

Are you trying to cram a couple of cats. into a long tube y-pipe or is it just a stock replacement? I would have to lean towards the mini-cats as being one of the smallest converters on the market. I got a pair from Pypes that I had welded into my off-road y-pipe.

 

how much did those Pypes cats change the loudness and tone of your exhaust as opposed to headers and an ORP????