I have a 2001 L with these mods: Superchips micro-tuner, FIPK Filter, silver bullet exhaust system and a 8 lbs lower pulley change. My boost increased up to 21 psi but why is it when my needle hits to the top on my psi boost, the engine sounds weird. Sounds like its losing its power. Any suggestions would be appreciated. Could it be an adjustment on my speed limiter, or rev limiter? Please help....