Cooling system pressure

[Tom Goldman]

I use Evans NPG coolant with a zero pressure cap.
my spare engine is an old Comp engine that has some heads that leak a little, not unlike some SS heads.
This stuff works great and is race legal as it is not an ethelyne glycole base and cleans righ up.
It boils at 360 deg F at no pressure and has a very low expansion rate.
not cheap, but it works great and can be reused for several racing seasons.






http://www.evanscooling.com/products/coolants/npg-2/

[Rob Petrie E395]

What is the advantage to running with no pressure?


On the Evans coolant do you have to run thier pump with it? At one time I thought you did.

[Tom Goldman]

the big advantage of no ,or low pressure ,is no pressure to force coolant into ports ot combustion chambers.
I run the Evans with a Mezire pump with no problems.
Evans has several coolants and they also offer thermostats ,pressure caps and hi flow water pumps,but I dont recall a specific requirement for using their pump.