Last month some of my family had come to visit me here in Mallorca ,Spain and i was carrying 4 people including me and 2 fairly heavy suitcases and i had to drive them to the hotel which was nearly 100 Km away on the other side of the island and there were a few fairly steep hills along the way and surely i noticed the temp gauge was quite a bit higher than usual, my fuel clnsumption was quite a bit higher too about 15/16 mpg when i usually get 20 or higher , this is with my Ford Capri, i guess it's not bad though to give the engine a good workout driving at high speed and getting the engine hot with these carbureted cars it helps to clean some of the carbon that inherently builds up, the next day i started it up again and it ran a lot smoother