Cooling fan HP losses...

[jayb]

Yes, both in the Galaxie and in my Shelby clone I use 160 degree thermostats and two electric Spal fans.  The radiator in both cars is also large, 31" X 19", aluminum with two 1" cores.

[Falcon67]

No electric fan will ever flow the cfm of a real fan.

Yea, they do.  OEM quality too.  Cheap in the yards, motors available at any parts store.

[jayb]

I was referring to a mechanical fan, not electric.  Sorry for the confusion.  Spal actually makes a lot of the OEM electric fans...

[Falcon67]

LOL.  I don't know who the OEM is on those but they came off an LT1 Camaro.  They work like gangbusters.  I can make a pass, come back at 200F or better, run the fans and electric water pump for 60 seconds and be below 180F. 

[Barry_R]

I know lotsa drag racers with electric water pumps and fans.
I don't know many that run them while doing a run.

I always run the water pump while making a pass.  Need to get the heat out of the chamber.

[Drew Pojedinec]

Sorry Barry, I was unclear.  I meant running the fans.

[Falcon67]

In the Falcon with the big fans, I run only the water pump during a run.  With a 31x19 radiator, don't really need them on a pass.  Same with the 300 HP 302 and the old 500 HP 351C.  The Mustang has a smaller radiator and small 10" fans, so it runs the fans as needed to control heat.  Driver preference (wife) on that one.  She just has one override switch to cool the car in the pit.  In the dragster, with the radiator behind the deflector plate, fan and pump run starting when I leave the Ready Line heading to the burnout box.  The water pump ALWAYS runs - the control switch panel in the dragster has two positions: pump, pump+fan.  In the door cars, ignition on = pump running.