Another potential and more serious issue with exhaust wrap is damage to the head, caused by localised heat not being able to be dissipated through the manifold,
Having said that, I wrapped the stainless steel primaries of my 2.3 260bhp Caterham when I built it in 2006, and suffered no ill effects up to the time I sold it last year, nor did the wrap break up, and the under bonnet temperatures were considerably reduced.
You just have to take a view, but I certainly wouldn't consider wrapping a mild steel system.
