I have finally found the information I needed to make an
attempt at calculateing how much water I need to properly cool my motor. The
latest edition of Circle Track has the best of S. Yunick which answered a
question on cooling which got me going on this. So here goes. Given::: 1 BTU is
the amount of heat required to raise 1# of water 1 degree F. 1 gal. Of
gasoline weighs 6.5#s. 1 gal. Of water weighs 8.33#s. It takes 1/2 # of
fuel/ H.P./hour. 1/4 to 1/3 of the Btus released durring combustion are
disipated thew the radiator or thew radiation. There are 19,383 BTUs/# in the
blue Erc A -8B 118 octane racing fuel or 127,940 BTUs/gal. So, for every
gallon burned you need 127,940BTUx.3=38,382BTUs of cooling or 5814 BTUs /# .
800H.P. requires 800H.P.x1/2#fuel/hr.=400#fuel/hr or 6.66#/min or .111#/sec.
It takes approx. 110 sec to run threw the 5 mile at 220mph, full throttle from
the 2 mile on, so this is where you are really using the 800H.P. I try to
correct for this later on. 110 sec. Run X .111 #fuel/sec. = 12.21# of
gasoline. You may use more than this because of running rich but I assume this
is all the motor really uses to produce the power??????? Soooooo. 12.21#s of
fuelx19683BTUs/# =240,329BTUs X.3 (the amount released into the cooling system)
= 72,099BTUs that you need to cool with water. Now 1 gal. of water wieghs
8.33 #s if it is iced to 40 deg. And allowed to raise to 220 deg. There is a
change of l80 degrees which would require 180X8.33=1500 BTUs per gal. to raise
it that l80 deg. So how much of a heat
sink (tank gallons) do we need.?? If the water was required to cool the entire
72,099BTUs we have Calculated we need to deal with ( please disregard the
blue and underline I really don"t have a clue how to run this thing) 72,099
BTUs devided by 1500 BTUs=48gal. of water required. If we assume the first
mile which takes approx. 36 sec to run (100mph. Avg.) the heat produced is
used to heat up the block and bring everything up to operating temp. then we
can changfe our calculation to a 75 sec run needing cooling. Therefor
75secsX.111#/sec=8.3# of fuel l9683BTUs/# X.3= 49,158 BTUs devided by 1500
BTUs / gal. water= 32.77gal. required . How much for you car??? 32.77gal.
devided by 800H.P. = .041 gal./H.P. or 4.125 gal/ 100 H.P. I know this is
more than most guys use , but I can't convince myself it's not what I need,
Ive got a 40 gal. tank I'm mounting behind my seat in the Salt Hawk. L.Kvach
Butters ending my longest typeing exersize in 30 years,..----------
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