|that the underhood heat is the reason for the fade.
There are also a number of other products that are made of fiberglass or other materials that may hold up better. I imagine some of the aircraft products might be better suited:
Try here: [ http://www.aircoment.com/products/wire-harness-protection/wrapable-sleeving/ ]
Would be interested to find out what you ended up using and how well it worked out.