One more overheating problem

My newest project is a '69 DART 440, .600 lift isky solid roller, headers, Be Cool radiator, aluminium high volume water pump,It does not run hot in town or at idle but got to 205 today on the interstate. Makes it want to vapor lock like an old flat head Ford. Any help would be greatly appreciated.

Well 205 mph will likely cause some high temps. Ice soaking it before a run is advised.