DO HEADER WRAPS WORK?

DO header wraps work?  is it just a waste of money?  

They work really great. Reduces heat under the hood and around the headers. You can even touch the wraps without getting burned. The only drawback that I have had is the headers will rust faster due to the fact that when it rains and the header wrap gets wet, it keeps the headers moist and promotes rust. Ofcourse, this is only an issue if your headers are not coated to prevent rust.  

Header wrap does keep your engine compartment much cooler, saves spark plug wires, and makes your car noticeably more quiet and smooth sounding. They seem to make my car run a little crisper in hot weather.  I don't know about making your headers rust faster, I have never noticed much water retention with mine.  They do, however, greatly reduce your header's ability to dissipate heat, making the header itself much hotter during operation than normal.  this leads to eventual brittleness and sometimes cracking.  I had a two inch hair-line crack in one of my header tubes once in  about 2 years after putting the wrap on.    I had my buddy weld it up and nothing has happened since.  Basically you need to be mentally prepared for possible problems and eventual header replacement if you wrap them.  It's up to you to decide if the benefit outweighs the cost/effort.  You might check header companies to see if wrapping voids the warranty.

I have Hedman thermal coated hedders, and they plainly state, in bold writing, that thermal wraps will void the warrenty.  

I used to work at NAPA and someone had a set of ceramic coated headers that I knew had ben wrapped. They had rusted through but there was a warrunty. So I sent em in anyway and the company honered them. But they wanted to see em first. I kept my mouth shut about the wrap and we got luckey.  

If your a competitive racer, header wraps will help find a couple extra ponies. Otherwise, they reduce header life and add to maintence problems, especially if your running with a catalytic converter, which will be driven to overheat and will burn out.

Bogie

Good point about the converter.