I am planning on putting a new exhaust system on my truck from the header back. I was wondering what size pipe you guys would recommend 2 1/4, 2 1/2, more or less? I plan on using a 40 series flowmaster muffler, and when I get enough money I am going to bolt up a LC header. I would like to find a good exhaust size that can be used with the stock manifold but still provide good flow with a header. Also i am going to ditch my cat until emissions comes around again, is there any negative effects to running with no cat? This if for a 93 toyota truck with a 22re