After searching 2 years worth of exhaust posts, I still have 2 questions -

Is the stock pipe size on a T100 exhaust system 2.25" or less? From the manifold to the exhaust tip, where exactly am I losing back pressure (aside from a leak) by going with the larger pipe? The exhaust system on my truck - 3 inch Walker Hi Flow converter, 3 inch aluminized pipe to a Walker Dynomax Super Turbo muffler and 2.5 inch side exit.

I've traced a small exhaust leak to the fitting before the muffler and before I bother to weld it, I'm thinking the 3" pipe is robbing my low end power and S/C, from the loss of back pressure. I may replace the pipe if possible and someone can back up my theory. The lack of initial throttle response compared to a friend's S/C'd Taco, with a stock exhaust, (taking into account the weight difference) has me thinking this system is the culprit. I appreciate any help as I try to figure out my next move -