I am currently in the market for a 2004.5 to a 2005 Duramax LLY Crew Cab 4x4. I plan on running a 4" Straight pipe with 6" Tip. Will this be loud? I want to get the most sound out of it that i can, expecially turbo whistle. Would a 5" Straight pipe be louder? Any help would be appreciated.