Dont do a straight pipe to no muffler or res. it sounds awful. loud as a f1 car and sounds like a honda fart rocket x3. I made a mistake of getting a custom fabricated weld on exhaust. it is a 2.5 in from the heard back. no cat, no resonator to a very free flow dynomax muffler.
First off it rices so hard. so much rasp.... it is soooo loud the drone at cruising speed is ridiculous.
2nd. lost all low end torque. our cars need some back pressure. the top end is awesome but so fucking loud and i dont drive in lift everywhere i go...
3rd. if you do not have the JDM ecu that does not read the 2nd o2 sensor for the cat you WILL have a permanent check engine light and you will run rich. (having this is the only thing i have going...) side note, the JDM ecu is tuned to 190 hp due to not having the cat or emisssions standards to comply with.
so my advice, get a trd, greddy, or magnaflow premade axle back. I just ordered a magnaflow axle back and a vibrant ulra quite resonator. im hoping once they are installed i get my low end torque back, and my diginity of not driving a fart cannon....