Like anything, there is no set point. At 146k and a motor swap you might as well while the motor is out as it's easier to get to. The turbos are cheap enough. Aftermarket? Only if you have someone custom tune for it. And then you might as well not choke it with the OEM downpipe. Heck drop a bigger IC in now since it would be running more boost. Injectors? Sure why not. See where I'm headed?