well i know to use high octain i was just thinking you may have used race fuel. i have a supercharged del sol and i only run 93 octain. but i just think that 400hp is crazy on a d series. but that turbo is huge. anothere question though with that turbo are you haveing to wait for it to spoil up or is it almost istantanius. i would think you would be waiting for the power almost.