dpantazis, You stated in an earlier forum that a bad MAF will result in less power and fuel economy and fooling a bad map with a boost pressure relief is pointless. How do you know if you have a bad maf? I'm guessing that a maf is a mass air flow sensor? Also, I am only getting 15 psi of boost out of my early 99. I just ordered a turbo master wastegate controller to get more boost. How are you getting 25-28 psi out of a stock wastegate?