Well the obvious answer is get the piping mandrel bent. But the nearest shop with a mandrel bend machine is about 200 miles from where I live..I think. How much more of a difference is there in performance between mandrel bent or regular crush bent pipe on a WRX running 15 psi, I only need like 2 bends...they are not even 90 degree bends. I also heard it is pretty expensive to get mandrel bends done. My friend got them on his prelude for 300 dollars for two 90 degree bends on 2.5 inch pipe!