Strange sound out of exhaust

[apospical]

I recently purchased an 05 Excursion, it has an Airraid cold air intake and a magnaflow turbo back exhaust with cat delete pipe in. When you stand back by the tailpipe, you hear a sound like pressurized air coming out of the tailpipe. Is this normal for a straight turbo back exhaust?

[RIStroker2000]

i know the 6.0 powerstrokes have a louder "whooshingg" sound exhaust stock.. and i can only imagine what it sounds liek straight piped... can you hear turbo and a whooshing, seemingly pretty loud? i would assume its the nature of the set-up.. check for cracks or leaks but i think you would know if they were present in exhaust

[FK000@aol.com]

It is normal to here a sound like that, damn near a whistle but not quite.
Goes away when you press the throttle...