My friends have been telling me they see flames or glowing coming from my exhaust when Im shifting at high rpms. I can hear it gurgle when Im shifting, almost like a backfiring sound, but not quite. Its like that backpressure sound from a real throaty exhaust. The only intake/exhaust mods are Mac cold air, Mac o/r H and Magnaflow Magnapack catback with 3.5 inch tips. What could this be? Do i need to get a bigger MAF? Do I need a chip to compensate for these mods? Am I hurting the computer?