Upon accelerating fast a noise kinda like its muffled if you will

Having issues with dart gt 2014 , upon accelerating quickly car begins noises , sounds like a muffled sound almost. Changed a dirty air filter . Oil and oil filter is new, changing out spark plugs. It has Lil over 80,000 miles. It also vibrates a tad bit when accelerating . In park you can not duplicate this it’s only when you are driving. Figuring it to be some kind of exhaust issue maybe , intake . I don’t know. Any ideas. Everything looked good under the hood. The sounds kinda are on the passenger side I would say. Thanks in advance:)

It’s hard to guess from this description, but it would be worth making sure the motor mounts are good.

What is “accelerating quickly”, normal start or really hitting the gas pedal? What vibrates, the body (car body, not yours), engine, steering wheel? Does it vibrate when hitting the brakes? Can you describe the sound a little better? Metal on metal, humming from front, rear, all over, does the sound change with the driving speed?

Might be some sort of pre-ignition. Replacing the spark plugs makes sense, as the gap can widen w/miles and contribute to this. Check for diagnostic codes too, esp any related to knock sensor or misfiring.