just got back from the exhaust shop, and he said my ypipe was a typical Nissan problem, and would cost about $325 to replace all the way to the Cat, and if the O2 sensor dosen't come out, another $80. the rest of my exhaust is just fine. he says if i want to bring in my own pipe (like warpspeed) it'll be $125 in labor plus anything they might need to mount it up correctly (studs, nuts bolts..) i was going to get a perf-ypipe and CAI anyway, but are the HP gains really worth the $200 CAI and $125 labor + price on warpspeed ypipe (anybody know the price) since i've heard that cattman ($335) is having some problems with theirs.
thanks for the help.

 

Install the Y-Pipe yourself.
Easy procedure with about 50 write ups on how to do it.
That'll save the 125, and if you want more ***** on your max then i'd say get them.