The old exhaust trick of drilling out the core plugs in the stock mufflers reduces heat in the exhaust system by a considerable margin since it spends less actual time within the system. It seems most noticable in the surface temps of the cans themselves. Of course, this trick pretty much permanently alters the stock cans, and lends the exhaust tone a more robust quality that's not that noticable except under hard acceleration. I'm in the Deep South and that cheap little mod made a big differenc