Just got a 5sp manual 2003 BA XR6T with a top and bottom rebuild done ~10,000km ago. Car is stock as a rock, apart from a heavy duty clutch and I was hoping to try and squeeze 270kw at the wheels. I've done some research and so far it's lead to me to believe I need 42lb Bosch injectors, Walbro 460 pump, Autotechnia intercooler, coldside intake/plumping and a dyno tune. However, I'm confused over if I need a highflow cat and upgraded valve springs if I'm trying to push the power I want. I'm trying to stick to a budget and don't want to spend more money than I need to.
Any advice would be appreciated, TIA.