Just ordered the ct racing sonic full exhaust for the raptor. The dyno chart is great,it grabs the torque right from the bttom and holds it longer than the other brands that were tested. Should work great with the big bore kit, cams, port & polish.I also ordered the lc1 from dobeck with the oxygen sensor for adjusting the fuel curve on the optimizer, A neccessary item with this setup to get it right.