Restrictive Mufflers

How old were those Accurate mufflers?? I have been told there are a different style with newer vs. older mufflers. I bought mine in 2000 and they look like your cutaway mufflers when I cut mine open too. I replaced those Accurate mufflers with a pair of DynoMax Super Turbo mufflers. With NO other changes, my GTS ran a full second faster in the 1/4 mile and picked up almost 4 MPH! I have since replaced the Accurate 2 1/4" system with a TTi 2 1/2" system X pipe with Ultra Flo mufflers. That was worth another .2 in the ET and 1 1/2 mph.