Which is better with a flowmaster muffler? Any ideas as far as if 4 inch outlet is to big or just the 3.5 inch, and about the length? Any help. No ideas what the sound differences would be.

Exhaust Tip, 2.5 in. Inlet, 3.5 in. Outlet, 18 in. Length, Polished Stainless Steel

Exhaust Tip, 2.5 in. Inlet, 4 in. Outlet, 24 in. Length, Polished Stainless Steel