Thanks for your comments. In the light of warnings about tightly-wound header wrap I've ordered one of these:
http://www.agriemach.com/c7-heat-and-sou...-cyl-straight-6It is not a constricting fit and seems to offer plenty of air/expansion room around the pipes. I'll also put some flexi alloy ducting over the rubber intake tube which will hopefully reflect radiant heat.
Expect pix/report in a week or so when I've got round to fitting it.
pip pip
