Muffler opinion

3" is way to big for a 318. 2 1/2 duel is even pushing it for a hopped up 318. 2-1/4 would yield better performance

Well I better inform my teener of that then.

Same here. I'm running dual 3" with an x pipe on my 5.2 in my Dakota. I have dynomax bullet mufflers right off the headers and magnaflow just in front of the axle. It sounds awesome. Nice deep tone at idle and not loud.