if you wanna go fast, then your gonna want to have 4/4 firearms and 4/4 speed on a new custom character. the reasoning will become clear later on

next, you gotta get these traits:
diminutive
skinny nerdlinger

finally, you only need two items:
accuracy mod
flamethrower

in order to vroom, you must walk in a certian direction and shoot the flamethrower behind you to get you maximum vroom

now you can vroom lol

infinite ammo not included