[JL8Jeff]

You might want to stop by a speed shop (if they still exist) or even check out one of the car parts places to look at the mufflers in person. The UltraFlo is a straight through just like a lot of the mufflers so they won't rob any power. The Random Tech I had on my 2000 SS was also a straight through and pretty mellow at cruise speeds but got loud at WOT. I had Hooker Aerochamber mufflers on my 68 and they were also straight through and were mellow at cruise speeds. They were kind of heavy though. Generally speaking, the shorter muffler case the louder it will most likely be. And a lot of the short turbo style mufflers are not straight through.