Engine brake

This might be a dumb question and there may be a thread already but nothing came up in the search; is there a way to "turn" down the engine braking, when I let off the gas I’m damn near thrown forward, my wife is thrown up against me. Seems pretty dramatic to me. 2nd question, anyone do anything under the back left fender for exhaust heat? Thanks everyone it’s a 16 Grizz..