In a message dated 10/22/2002 12:21:09 AM Eastern Daylight Time,
canarder@starband.net writes:

> AMEN brother Leon !!!
>  That said :o) ... What are your thoughts around brother Tracy's notion
>  that controlling temperatures by lowering the pump output to pump less
>  coolant would result in higher temperature gradients from inlet to outlet
>  of the block?  One might intuit that the EWP is efficient enough to run at
>  capacity and still have efficiency advantages over stock system, so why
>  not either bypass coolant around the radiator or use cowl flaps for
>  coolant temp control.
>  Makes sense to me .... Jim S.
>  
I just cannot keep my mouth shut about this. All of the coolant going through
my race engines, (about 245 HP at 9,400 RPM) must pass through a 5/8"
restrictor.
The opening is in a flat aluminum plate welded over the end of the water
outlet on top of the water pump. It (the outlet) happens to be off of a
Spitfire, but could have been off of a Mazda. It makes no difference. The
hole in the plate has sharp edges. From watching test pieces on the flow
bench, I would suggest that it flows about as much as a radiused 1/2" hole or
maybe a little less.  My empirical data suggests that the maximum flow rate
of an unobstructed stock pump is maybe 4 times what is required to cool the
engine at speed. It has to be so lest it not save the engine after a long
pull at speed and a drop to idle speed for a long period. It has to move
enough water past the hot spots at IDLE speeds or the engine would be ruined
after the first run up over 100 MPH. And don't tell me you never had it over
100. I know you better than that. I will not be amazed if the electric pump
works. I will be amazed if it doesn't.
Lynn E. Hanover