Evolution of the sports car starts here:
The original radiator core was replaced with a smaller, modern core when I reduced the height of the radiator by 100mm. Although it was smaller, the new core was always likely to be a lot more efficient than the 30’s design. You may also remember that I reconstructed a water pump from another vintage Riley believing the radiator by itself may not be enough to keep the car cool. It transpires that the ‘upgrades’ are both jolly good at their job and they are too efficient. The car when driving doesn’t actually go above 55 degrees. Modern cars have a thermostat to quickly warm up the engine and that thermostat opens at 90 degrees. What this means is that the engine in my car never gets to operating temperature which effects the efficiency and the power because I need to run the carburetors rich to counter the cold fuel.
Even driving the car in the recent heat wave made very little difference, a 30 mile drive barely moved the temperature gauge off the stop. But I grant you I have not had to sit in static traffic for very long and having no fan, I would eventually have a problem in traffic. However, I need to look at what I can do to improve the situation. Initially I am looking at the cheapest option of inserting an inline thermostat into the engine-radiator hose so that the water in the radiator is basically isolated until the engine warms up. I rather suspect though that this option will simply mean that once the thermostat opens the radiator will rapidly cool down the water too much again.
It is quite possible the final solution may be to remove the water pump reverting the cooling to the principle of thermo-cyphoning (circulation occurs due to hot water naturally rising which pulls cold water into the engine at the bottom) and having an electric fan for the stuck in traffic occasions. We shall see over time…