necessity of having a nismo thermostat

[g6civcx]

Originally Posted by TheRealNighthog

The point of bottle-necking the cooling system with a thermostat is to create higher than normal atmospheric pressure in the cooling system

Does the water pump have anything to do with raising coolant pressure?

Originally Posted by TheRealNighthog

Notice that the bottle-necking only occurs before the coolant re-enters the block and obviously after it has circulated through the radiator.

I'm no expert in fluid dynamics. Does the pressure equalise as soon as the thermostat opens, assuming the appropriate loss of course? Is the water pump forcing coolant flow through the system?

Originally Posted by TheRealNighthog

the spring in the radiator will not let any of the coolant move to the overflow reservoir until the cooling system reaches a certain pressure.

Can you describe a little more how the radiator cap works?

Originally Posted by TheRealNighthog

The block has to stay at a certain temperature, which is why the need for the thermostat. That's why the needle on the temperature gauge shows the coolant being colder than normal when you have no thermostat in place.

What's the reason why the needle stay low?

Originally Posted by TheRealNighthog

The various ratings of the thermostats help ensure that you reach the maximun highest temperature goal that you have in mind. And when that doesn't help, then come fans to help reach whatever highest temperature it is you want it to be at.

What do you mean it "doesn't help"?

[TheRealNighthog]

Does the water pump have anything to do with raising coolant pressure?
Of course. The pump is the source of the pressure.


I'm no expert in fluid dynamics. Does the pressure equalise as soon as the thermostat opens, assuming the appropriate loss of course? Is the water pump forcing coolant flow through the system?
People assume that coolant flow is insufficient or being blocked all because of the diameter of the thermostat opening hence why some people assume that running an open thermostat will help with cooling. They think Bigger=better. Im not sure on equalized pressure. You would need a way to measure it pre and post thermostat. Bottlenecks or venturis how ever do help in pressure and velocity depending on the application


Can you describe a little more how the radiator cap works?
here you go. This might help. lol
HowStuffWorks "How Car Cooling Systems Work"





What's the reason why the needle stay low?
I dont like to use OEM guages since they either read hot or cold or somewhere in the middle. I use all aftermarket guages since I like to keep close tabs on all functions of my motor. When you run no thermostat you are allowing coolant to flow at all times with no control over it. The purpose of the thermostat is to open and close at determined temps to keep the temps in check. There is an optimum operating temp for our motors, and its def. not optimal to run too cool. I am thinking that I worded my thoughts wrong.



What do you mean it "doesn't help"?[/quote]There might be times when the rad by itself might not be enough due to either driving condtions, cooling system condition, or external conditions such as high temps or stop and go traffic. Thats where the fans come in, to aid the rad. in heat exchange.