I have an electric cutout on an otherwise stock exhaust with heads/cam...its time to upgrade to headers. My question is will the car be louder or quieter with headers/duals/mufflers than with the manifolds/open cutout?

I've checked out ls1sounds.com (great site), but it is hard to get an apples-apples comparison with different videos.

Setup I'm thinking about -> QTP headers, x-pipe, dual 2.5" exhaust over axle, 7.5" mecham oval tips. Mufflers I am still debating on, and I know these will make a big difference. Edelbrock 304. Sweet Thunder pipes. Any other suggestions? I want a deep sound. No rasp. Doesn't have to be Nascar - I'm going for more old school. Think the sound Elanor has when idling.

 

It will be louder with headers, duals and mufflers because you wont have cats. My friend had a cut-out on stock manifold/cats, and it wasn't all that loud.

 

Depending on which cat back (or on which mufflers you choose in a true dual set up) is chosen I agree...I have a pure stock exhaust (stock internal motor though) with a cut out and it's not all that loud relatively speaking.