I see on jc whitney (ebay, etc also) some sort of aluminizated tape for cover the exhaust manifold and prevent hot temperature on the engine bay. Using it, and by the same token, the hot temperature remain into the manifold... if your has inlet and outlet manifold interconnecter (the hot plaque), could be usefull to cover with that tape the exhaust manifold to promote the heat transfer without heat loss on air.

(my excuses for using spanish phrases with english words).

Joaquin
Rojo 121 Amazon
Lima Peru
(12 to 30 degress celsius all year, I use the choke or press 2 times the accelerator for saturday starting - by now I use the rojo only on weekends)