Wait a minute there Pardner, we already got you covered on that
topic here at Club-tC. You need look no further, but we do appreciate the info.
And to elaborate on what MkhoiD said: Bigger is not always better. There is a science to exhaust dynamics. May not be exact (too many variables), but nonetheless, a proven formula to extracting more power from an engine thru efficiency. A pipe is not a pipe when you look at the material used, diameter, wall thickness, bends, obstructions, burrs, and length. I won't go into detail in this as it has been discussed before in other threads. Things to consider when choosing a header on the tC are 4-1/4-2-1 designs, whether you are N/A or S/C, equal length tubes, how low does it hang, and whether you are keeping the stock mid-pipe. Backpressure plays a bigger role on the positive side for N/A and the TRD than is generally understood. Turbos are completely different animals in terms of exhaust design.