Intake manifold SB
If the engine has over 60 thousand miles on it my advise is don't. Here's why... So many times those external bolt ons , intakes, 4 brls, headers, etc.., are added then the bottom end comes apart. Changing the air flow changes back pressures and wear patterns.
The improved throttle response and even the new sound will prompt the driver to stomp the fire out of an engine that might otherwise have ran well over 100 thousand miles.