I have seen 0.040 with stainless and 0.06 with aluminum. Use Fiber Frax. It comes in to thickness's.
Hope this helps Cheers M. Greg Martin > > Dan Heath wrote: >> What thickness and alloy is being used now, for the firewall. I will be >> re-surfacing mine when I install the Corvair and will use Stainless. >> Also, >> what is the insulation material that is preferred. >> >> >> >>
