You have the z1 dual intake kit and the ashspec planar inlet kit? If you have both then sell the z1 kit and install the ashspec since it will give you more power. As far as 2.5" intercooler piping, Ive installed an ashspec and I installed the z1 on my own car. Ashspec kit had far better fitment. The z1 pg exhaust will be very loud but if that doesnt bother you then go for it. I would also suggest MSP manifolds since you are going to pull the engine for the turbos. You will need a selin translator for the ash planar inlet kit.