per Cap'n Bob...
>>Then someone, please...
>>
>>.....explain the racer who finds himself running hotter at
>>higher forward speeds and cooler at lower forward speeds,
One possiblity I've heard of but not seen mention here yet is the air itself
compressing and impeding the flow through the radiator core.
Apparently it's easier to suck air through a restriction than try to push it
through.
When the fan is behind the radiator it only creates a vacuum and as much air
as possible is encouraged to flow through the core as fast as it can.
When the air is pushed through the radiator from in front it runs into the
fins and tubes and gets knocked out of a smooth flow, slows down and gets in
it's own way. More air is 'pushed' into it from behind and you end up getting
the air (slightly) compressed and further impeding the flow. Kinda like The
Three Stooges all trying to get through a door at the same time. :-)
The Ford Fiesta took advantage of this with the shape of the slats in it's
front grill. At higher speeds, where less air is needed, the airfoil shape of
the grill slats would compress the air and cause more to go over and around the
car rather than through the engine compartment.
Ed in NC
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