i just put new ngk wires and plugs. new dizzy cap and rotor. and new fuel filter (it all needed to be done anyways). tonight or tomorrow i will be running the temp test on the cat and what readings the o2 sensor is giving also. i am suspecting the cat due to the wrx sound. plus once everything gets hot, it dont seem like much exhaust is coming out the muffler. im running a obx exhaust on it. i also just adjusted the valve lash this morning cause the motor has about 15k since the complete overhaul. the thig that still has me stumped is that it NEVER burned oil till the header install. if that cat is clogging up it could suck oil past the valve seals and guides for what i have read. mainly just trying to see if anyone has had this weird problem before and what their fix was. ive been researching for 2 days trying to figure it out.