Ok so I have An 04 WRX with a lot of mods bought her a week ago. The only mods I know of are lightweight flywheel, 6 puck clutch, blouch 16/18 g turbo, 660cc Injectors, 3 in up and dp. she's pushing about 268 awhp. When under acceleration my car bobs and shakes and backfires while accelerating while losing power. And for some odd reason it'll just go away by itself or if I let it alone for a while and restart it its better for a little while. No fuel spitting out the exhaust or black or blue smoke. Oils are good. I'd really REALLY love some help. I'm new to Subaru and turbos honestly. Teach me something. I'm starving for knowledge.