After blowing my relatively new (47,xxx miles) D15B through means of a good turbo kit, I'll never do it again. I was only running 5-6lbs of boost, and that lasted only 3 weeks of rarely driving. And I never drive my cars hard either. Goes to show you how bad the rods are in those engines. So for a little advise, I suggest doing a lot of bottom end upgrading before anything. Strictly all motor for me.