That guy keeps sending me emails wanting to know if he can advertise on my site, I don't reply simply because I have no problems sealing up my exhaust using silicone, they never leak http://www.pilotodyssey.com/Siliconesealer.htm

That AND the stuff he is selling for 9 bux looks to me like valve packing material, the graphite impregnated rope or the graphite/teflon rope used to pack valve stems on industrial valves. .

If you cant make your exhaust seal up you might give it a try...

http://www.johnsonpackings.com/sealing/pvpack.htm