Bruce A. Frank wrote:
snip
I have recorded data myself during a several hour test period of a 3.8L
engine, installed in a WagAero 2+2 Sportsman. WOT testing was done to
ascertain ability of the fuel system to supply the engine; ability of the
radiator to cool the engine and fuel consumption.
snip
The engine was started and gradually pushed to 3000 rpm until water and oil
stabilized at thermostatic temp of 195 degrees. The trottle was advanced to
wide open and the leaning block adjusted to obtain a maximum engine rpm of
4400. After 5 minutes at WOT the water temp advanced to 200 degrees F and
the oil temp to 220 degrees F. where they stayed for the remainder of the
run. Fuel flow at WOT was 15.6 Gal/hr. THe engine ran at WOT for 30 minutes
then was throttled back to 1500 rpm for 5 minutes then shut down by using
the lean cutoff setting. When cut back to idle coolant temp jumped to 225
degrees F and oil temp rose to 225 degrees F.
We felt from these results that the Taurus radiator was adequate to cool
this engine. Weeks later while flying this combination on a 100 degree day
it was possible to obtain 4700 rpm at WOT and was maintain for 15 minutes.
Water temp reached 215 degrees F and oil temp reached 225 degrees F and
remained there for the balance of the WOT flying test(oil temp is measured
in the pan). Upon throttle back both oil and water temp returned to the
thermostat temp of 195 degrees F. This radiator seems fully capable of
handling the heat generated in this application with power production in the
130 to 190 hp range.
Bruce A. Frank
BTW, the racing rad that Griffin produced for the Busch racing circuit, when
the 3.8 was in use, is the dimensions as the Taurus two row radiator. This
OEM radiator bought new from Ford is over $480. I bought one new from a
Modine distributer in Wilmington DE. for $165 seven years ago. The price in
two salvage yards I called today was about $50.
We are missing some information here. What did the duct look like,
the altitude, the outside air temp and the airspeed at WOT?
Bruce when you get a chance please check and see if the tubes run up and
down
in this rad rather than back and fourth. The rad is too big to use, as
is, in a typical low wing airplane. I would like to see if it is worth
cutting in half and using both halves in the cowl or back to back
in a P51 type scoop.
Paul Lamar
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