.034 gap should be fine for your application so I doubt that it is causing you this headache. If you changed the pulleys to increase boost that could have an effect. Also be careful doing so on a PD blower. You may be causing more heat soak with spinning the blower harder and this can really spike the IAT's. Do you have a way to monitor them while you are driving? There are tables that base timing/fuel on IAT. If you have increased this to a range not expressly worked on inside the tune this may be your whole problem. Try changing the pulley back (if you have recently changed it) and see if this clears up. When it comes to boost, some times there is such a thing as too much