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The Gorilla · 18-01-2014, 02:11 PM

Hi,

Quote - ''...US car in California have same issues and I doubt they run any antifreeze....''

I doubt they do also but that's the point
as anti freeze has a higher boiling
point than water on its own.

The fact that Oil goes up first and water is
stable, and then water starts to rise will
be caused by the Thermal store [engine]
temps rising beyond the water jacket limits.

In say 28c + ambinet air temp, then the surface
area of the std coolant rad must be almost at the
upper factory limits for the water temp at say 80%
engine load to rise and only fall, when engine load
is decreased.

Hence even a 10 or 15 % increase in airflow, given
the ambinet air temp of 28c +, will do little to lower coolant
temp, either a greater coolant rad surface area so the
coolant limits are increased to dissapte more heat
under high load or the coolant itself must be able
to absorb more heat without boiling.

Think of your central heating system at home
say a 120,000 BTU boiler running say 12 rads putting
out 85,000 BTU, say 14,000 for the hot water cylinder
and it copes to say -8 or 9 now drop the external
temps to say -25 and the 20,000 spare BTU capacity
would be very marginal in maintaing say 75 in the
living rooms and 70 in the bedrooms.

Remove say two rads by shutting down their rad
valves and the overall system gains back say another
10,000 btu's with which to assist in mainting required temps.

I think your correct that in heavy load situations with
higher ambinet temps the std coolant set up breaches
its factory limits, Oil temps start the process by increasing
the thermal mass temps [engine] and then the coolant
starts to struggle keeping within limits.

Its in part why I went with the Heat exchanger and the
Tropical stat as the combination of the two lowers
my normal operating temps on both water and oil
giving a greater margin for when ambinet air temps
are hotter which when combined with a few air
flow alterations and good concertration of Anti freeze
has seen no real coolant issues to date.

Another point on air flow, is that the M3 Alloy lower subframe
Brace and the front undertray prevent any real airflow
around the sump.
Some airflow to the sump would also assist in keeping
oil temps down.

Regards,

The Gorilla.

18-01-2014, 02:11 PM	#66
The Gorilla S5, Sport Off, DSC M-track Join Date: Apr 2008 Posts: 740 Casino cash: $14401	Hi, Quote - ''...US car in California have same issues and I doubt they run any antifreeze....'' I doubt they do also but that's the point as anti freeze has a higher boiling point than water on its own. The fact that Oil goes up first and water is stable, and then water starts to rise will be caused by the Thermal store [engine] temps rising beyond the water jacket limits. In say 28c + ambinet air temp, then the surface area of the std coolant rad must be almost at the upper factory limits for the water temp at say 80% engine load to rise and only fall, when engine load is decreased. Hence even a 10 or 15 % increase in airflow, given the ambinet air temp of 28c +, will do little to lower coolant temp, either a greater coolant rad surface area so the coolant limits are increased to dissapte more heat under high load or the coolant itself must be able to absorb more heat without boiling. Think of your central heating system at home say a 120,000 BTU boiler running say 12 rads putting out 85,000 BTU, say 14,000 for the hot water cylinder and it copes to say -8 or 9 now drop the external temps to say -25 and the 20,000 spare BTU capacity would be very marginal in maintaing say 75 in the living rooms and 70 in the bedrooms. Remove say two rads by shutting down their rad valves and the overall system gains back say another 10,000 btu's with which to assist in mainting required temps. I think your correct that in heavy load situations with higher ambinet temps the std coolant set up breaches its factory limits, Oil temps start the process by increasing the thermal mass temps [engine] and then the coolant starts to struggle keeping within limits. Its in part why I went with the Heat exchanger and the Tropical stat as the combination of the two lowers my normal operating temps on both water and oil giving a greater margin for when ambinet air temps are hotter which when combined with a few air flow alterations and good concertration of Anti freeze has seen no real coolant issues to date. Another point on air flow, is that the M3 Alloy lower subframe Brace and the front undertray prevent any real airflow around the sump. Some airflow to the sump would also assist in keeping oil temps down. Regards, The Gorilla.