I posted this back in July on Samba and a similar post here on the list:

http://www.thesamba.com/vw/forum/viewtopic.php?t=308952&highlight=exhaust+wrap

I have about 30 feet of wrap left.  Any takers?  ;-)

2008/11/10 Jonathan Poole <jfpoolio@gmail.com>:
> Howdy List,
>
> This may have been covered but I thought another reference wouldn't hurt.
>
> When I installed my Boston Bob 2.0 Air-Cooled motor last year I went over
> every component and replaced/refurbished as best I could.  That work
> included wrapping the exposed header pipe that runs from the heads to the
> heat exchanger cover.  I see this sort of wrapping on a variety of engines,
> especially of the high-performance flavor so I figured it had to be a good
> idea.  I also had hopes of warmer cabin heat since more heat would be
> transferred into the heat exchangers and I had hopes of cooler heads
> (maybe).
>
> What ended up happening was that the header pipes melted and cooled
> repeatedly.  A week or so ago I developed an exhaust leak which turned out
> to be a cracked header (under the fiberglass).  When I tapped on that header
> it crumbled.  I pulled both heat exchangers and all 4 header pipe sections
> that had been wrapped were easy to tap holes into and chip/crumble to bits.
>
> I have since learned that I am not the only one to experience this problem
> on an air-cooled VW.  A local air-cooled VW machinist reported of hearing
> about similar melting headers when wrapped.
>
> If anyone wants to see pictures I have a few that I can p-mail or post
> somewhere online.
>
> Jonathan Poole
> '83 AC Westy
>

--
Chris S.
Disclaimer: "Death and serious injury may occur"