TTi step vs. 340 manifolds

man I cant really answer that I remember thrush hush and thrush turbos but they aren't like glass packs...I have installed accurate "factory" style exhaust and mufflers on my 340 swinger and I like the way it sounds, its different than my Fox body mustang for sure. Im noit saying go wo9ith accurate but I like the sound of them . i think because Im hell bent on my car being as close to original as can be i just like it. i did have 2.5 inch with headers and walker dynomax and that sounded like a drag strip on the highway opened up. Point is pipe diameter has something to do with the sound I think,...