Header wrapping used to be somewhat of a black art. The goal is to keep the hot exhaust gases flowing, and wrapping the pipes with an insulating barrier helps keep the heat in. The side benefit is that properly wrapped headers can help keep under hood temperatures down as well. The challenge is to use the proper material and wrap the headers so that they are not only functional, but they do not look like a bandaged mummy when finished.  In this video, Dan Stark from DEI shows us the right way to wrap headers using their Titanium Header Wrap, stainless ties, and the cool new tie wrap tool to keep the heat under wraps.  See more at http://www.designengineering.com/ .