I didn't do too well at Reno either. I had the runs, the car didn't.
;=) The car ran, but is apparently very sensitive to altitude.
In a race motor that spends much of its time near redline, localized
heating around hot spots (like in the head) can lead to cracking. This
is the reason Redline Water Wetter sells so well. It reduces the
surface tension of the water, making for smaller bubbles, and keeping
more water in contact with metal. The higher pressure will also make
less localized boiling occur. The farther away you are from boiling over
the less likely you are to have localized boiling. Some modern race
motors run 21 lb caps!
There are other things you can do to improve cooling, such as electric
fans, radiator cores with more tubes, turning on the heater, etc. Many
race motors also run without thermostats, and it is recommended to put
in a flow restrictor downstream of the water pump (or in place of the
thermostat) in order to prevent cavitating the pump. Cavitation can
occur if the back pressure on the pump is too low, and the spinning
impeller starts generating bubbles, that decrease the efficiency of the
pump, leading to less cooling, leading to more boiling, which causes
more bubbles, leading to less pumping, etc. etc. etc. Bleeding the
cooling system of any trapped air is also crucial for race motors.
> Following a bout of overheating (and I might add overeating) at Reno, I
> was advised to install 14 psi cap on my 1960 vintage race MGA.
>
> In my case, it seemed a much better plan to fix the overheating problem.
>
> Are there any advantages to a higher boiling point other than delaying
> boiling over for 2 more minutes? at a potential cost of blowing a freeze
> plug (done that) or a hose (done that)
>
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