I've been going crazy trying to get the F250 to sound as tough as it looks... Ravin 55 replaced the stock muff... nice, responsive throttle improvement and what seemed like more bottom. Hated the raspy 6 banger sound. (kept stock 3" pipe)

Replaced the Ravin with a DeltaFlow 40. Deeper sound, immediatley noticed the bottom end was softer. Still sounded too raspy.

Did some reading here (thanks!) decided to try a turn down a few inches after the Flow Master. Mandrel bent 45, slash-cut end. Pointed straight down, too loud, but not rapsy! Rotated it a little to the outside, PERFECT! Bottom end is back! Deep growl, just what I was looking for.

(exhaust dude made me a slip on that will allow me to mount the tailpipe back on should I get called for emmissions testing) Seems they won't get under the truck to hook up the hose.

What's weird is, you would think the loss of the tailpipe would cause even more loss of bottom, but it had the opposite effect. Muff guy (custom shop) says in a 3" system, the vast majority of back pressure is in the cat (250's only have 1) and the muffler. I really don't have a clue, but I can feel the increase in the seat of the pants. Go figure.