or just put up with driving a rhd, i have for a couple of years now I might convert it if i go ahead with a V8 conversion, use a lhd disco for some doner parts.
thats why I mentioned a leak, if there is not a flow of air the heat should not travel up the pipe so much
try a different pipe if all else is ok
I used some normal 6od air hose for my boost pressure gauge and never had a problem with that