ok i wanta know if anyone has a real answer, is the flowmaster or the imco and other muffler brands louder than a str8 pipe

 

No, I don't believe any muffler will be louder than straight pipes. Hence the word "Muffler". I always recommend mufflers over straight pipes anyday. A well built exhaust system with a quality muffler will add HP and Torque. Straight pipes, though louder, will rob your truck of HP and Torque. So your truck will sound fast and Bad A$$, but won't be able to back it up. Why do something that will hurt the performance of your truck. I love the sound of a nice loud rumble just as much as the next guy, but you can get that with the right setup.
When I here a guy going down the street with straight pipes I just think to myself that he must be too cheap to do things the right way.

 

Yeah, performancewise, straight pipes aren't necessarily the best. Although, what if you went with a smaller diameter, say 2" or so? I still like 'em though...I had a friend in high school who had a Camaro with TPI 305, 5-speed, and straight pipes...that was one of the best sounding cars I've ever heard.

 

I must admit I've heard some really great sounding cars/trucks that have straight pipes, not many, but some do sound great. The F-150 is one of those trucks, because of the 4 cats. But still, it will definitely hurt performace and I don't see why anybody would want to make a truck sound great but not perform the same.