Keep the mufflers and get a high flow h or x w/ cats. It will quiet it down significantly. I understand your situation. It is easy for someone on here to say "F *** that guy." However, you are the one that must live next to this guy and you have to ask is it worth it to battle with this guy after being in your new house after only two months? You can put on some high flow cats, quiet down your car, say to this guy " I spent $400 on my car because I want to show the people of this neighborhood that I respect their peace and quiet." You have done your good deed and shown you are attempting to cease any problems with your neighbors. If there is still a problem after that then you say F*** you, take off the cats, put on the off-road H, buy a line-lock button, and start smoking in front of this guys house. Good luck. There are no winners among the battle of neighbors.