most people don't know why overheating is bad, so let's basic that - overheating is bad because the water turns into a gas and given the combustion temps of 700-900 degrees, it literally melts the head gasket and induces stress fractures in the block due to rapid spot heating. The block heats, it closes the gaps that allow such things as pistons to move (since iron and aluminum expand at different rates).
a pressure cap raises the boiling rate at sea level by 1 degree per every pound of pressure. Thus, a 15 psi cap raises the boiling point to 227* at sea level. The further above sea level the lower the boiling point.
with me so far? excellent - water does two things: it evens the temperature around the combustion chambers (thus controlling thermal expansion), and it transports the heat away. It is not the most efficient at either but it's benefits outweigh its detriments. If you can keep the water from boiling, a motor can run well into the 300 degree range without adverse effect. Enter Evans coolant - if you're bouncing near the boiling point, that is the time to spend for Evans coolant. With that said, oil is a far better at removing heat and transporting it away - thus, before Evans, I'd highly recommend an oil cooler. Lots of race cars rely on water to maintain even temps in the head, they fill the block with hard bloc and use oil as the main tool to transport the heat away (of course, it's also flammable, so there is downside in cars that do not see constant maintenance). That said, Any turbo car I've built have oil coolers because it is so good at moving the heat - to the point that one of the cars I built we had to reduce the size of the oil cooler because it was working too well (think of oil as the heavy-lifter and water as the fine tuning).... I don't have an oil cooler because packaging would be problematic so I use Evans - but it's $250 minimum to change and you can never put water in it without having to spend $250 again (so avoid poking holes in the radiator)....
a pressure cap raises the boiling rate at sea level by 1 degree per every pound of pressure. Thus, a 15 psi cap raises the boiling point to 227* at sea level. The further above sea level the lower the boiling point.
with me so far? excellent - water does two things: it evens the temperature around the combustion chambers (thus controlling thermal expansion), and it transports the heat away. It is not the most efficient at either but it's benefits outweigh its detriments. If you can keep the water from boiling, a motor can run well into the 300 degree range without adverse effect. Enter Evans coolant - if you're bouncing near the boiling point, that is the time to spend for Evans coolant. With that said, oil is a far better at removing heat and transporting it away - thus, before Evans, I'd highly recommend an oil cooler. Lots of race cars rely on water to maintain even temps in the head, they fill the block with hard bloc and use oil as the main tool to transport the heat away (of course, it's also flammable, so there is downside in cars that do not see constant maintenance). That said, Any turbo car I've built have oil coolers because it is so good at moving the heat - to the point that one of the cars I built we had to reduce the size of the oil cooler because it was working too well (think of oil as the heavy-lifter and water as the fine tuning).... I don't have an oil cooler because packaging would be problematic so I use Evans - but it's $250 minimum to change and you can never put water in it without having to spend $250 again (so avoid poking holes in the radiator)....
