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Subject:Coolant pump specs
From:John
Date:Sun, 4 Feb 2001 23:45:26 -0500

Hi Steve,

I agree with you that such info may be interesting but since the volume
only varies with RPM it can't correct any problems. On my '86 Syncro I
have coolant temp sensors on BOTH sides of the thermostat and I can
switch from one to the other with a toggle switch.

Excluding sitting at idle RPM with 0 MPH and NO ram air at the radiator,
the thermostat must actually put the brakes on the coolant flow. On a
30*F day at 70 MPH the engine temp is at 190*F and coolant on the other
side of the thermostat is ~45*F. If the T/stat didn't hold the radiator
coolant back, the normal 4K RPM coolant pump volume would OVERCOOL the
motor. All coolant pumps overproduce and it's the thermostat's job to
limit the cooling ability by blending(recirulating) hot coolant with the
cooled coolant returning from the radiator. This dual coolant sensor
setup really showed me how effective the WBX cooling system is when it's
free of defects.

Regards,    John

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