I took my Mustang into a "reputable " muffler shop looking to upgrade my exhaust, the exhaust is aftermarket, turns out there's no mufflers at all, just "X" pattern dual straight pipes with dual cats (catalytic converters for us California smog check victims ") I have never had a car without mufflers and is it safe, legal? I want a muscle car rumble and it sounds good now but it's lacking the deep rumble to match my little 4.6 what exhaust system is good? If someone can educate me about straight pipes and exhaust I would appreciate it, first Mustang

 

Man, that must be LOUD!! Most states require a 'muffling device' so definitely install something on your Mustang. I'll let others chime in on what sounds good. I'm a 'stock' guy and have no advice on that.

 

I hear that the catalytic converters muffle most of the sound, it's not illegal sound, I hear 4x4 trucks louder than my Mustang