Best glasspack to run?
Been running straight pipes since the 70's and have never had ticket....but, I also run a full system all the way to the bumper and that helps. Did have a 66 Mustang Fastback with a mild 289 with Smithy's Green Power glass packs that exited out in front of the rear tires. All those things did was amplify the noise lol. You can also tone down a straight pipe system by using a larger diameter pipe and add a lot of crimps to it. Doesn't hurt the flow either....boundary layer air is slow anyways and the center layer is what moves and the crimps help to reduce the sound waves. I've found some mufflers shops had crimping dies but don't know of any around here anymore. Most of the mom and pop exhaust shops have closed down. If you use 1/4" deep crimps, add 1/2" diameter to the pipe you use to crimp. The last one I did only had 1/8" deep crimps and were done with a muffler clamp (pita) in a 36" long pipe but only did 7 crimps. Made a difference but not all that much. One of these days I'll make my own crimping dies.