Gents, if you look back to the results I posted from my day at Goodwood with the GRS, you'll see that out in 'real world' airflow, heat soak isn't really a
problem.
When I got back into the pits I opened the bonnet and the manifold was absolutely stone cold, despite the 6K RPM per gear out on circuit.
Come back 5 minutes later, the manifold is too hot to touch - which demonstrates how much cars on RR days must suffer.
It seems that with good charge cooling, the inlet manifold acts as a heat sink for the cylinder head. Kinda makes me think things like power gaskets might be counter-productive while on the move?