whoa there. i think you need to learn a lot more about turbos and engines in general if you intend to build a turbo engine. because what you just said there shows you dont know a whole lot. the greddy kit comes with a small T28 i think it is turbo. i dont think a T4 will even bolt to the manifold the greddy kit comes with. i'd get a drag or other kit with a bigger turbo and better components. or piece together a custom kit. an intercooler is most definitely needed if you're boosting more than 10 psi, which you'll need to do to reach your power goals.