I just had a set of BBK long tube headers installed on my 2003 Roush stage II convertible. Before installing the headers I had a BBK off road catless x pipe with Dynomax Super Turbo mufflers. They were loud, albeit a bit raspy between 2000 and 2500 RPM. I just installed the headers today and although the tone mellowed out and it's no longer raspy (sounds awesome) my exhaust system is much more quiet, nowhere near as loud. Is this normal? I thought headers were supposed to open up the exhaust and give it more "oomph"!!!!

 

it probalby did open it up and with more air just smoothed everything out. I have BBK shorty's going to a magnaflow high-flow catted-x then to dynamax side exhaust. With the motor stock except the intake/exhaust it was very raspy.

This was the sound clip from the my car the day I got it back with the exhaust.

http://www.youtube.com/watch?v=vteaWtW-BDs

now last summer I put trickflow twisted wedge 170 heads, a stage 1 cam as well as an anderson power pipe and 90mm lightning maf. After all that was installed it certainly changed the sound as now it has a lope to it but it also took out all the raspyness that I had for a much smoother cleaner note. It is louder as you can tell its moving more air but the rasp is gone.