I have an lq9 swap in my 95 Chevy. Exhaust manifolds into flowmaster collector single 3" all the way back no cats no smog.. I started with a flowmaster 10... Way to loud at throttle.. Moved to a 40. Still has a crackling shitty sound. Heard magnaflow was what I needed.. Bought a 7" round .. It is crazy. Worse than the flowmaster. What do I need ? I love the sound of the shorty mufflers at idle. But driving kills me .