I remember an article in Hot Rod (way back around when when Dave sourced his
information) about grinding off every other vane on the stock Ford water pump
for a high performance engine. If the stock Ford pump has six or eight vanes I
can see this working out to the roughly 50% Sparky is using as a good figure.
I'm not a flathead guy so I have no idea on what the stock pump has. At that
time I got some really interesting answers when I asked about it, mostly
speculation or evasive answers so I figured it was a "speed secret".
Wes
> The guy at Stewart---told me to turn the pump as close to 52-53 max as
> possible---that why the sprint car guys have up to 30% reductions possible
>with
> different pulley sizes
> >
> > From: <dthomssen@neb.rr.com>
> > Date: 2005/03/14 Mon PM 09:15:19 CST
> > To: "Land-speed Racers" <land-speed@autox.team.net>
> > Subject: Fw: Am I crazy or just dumb?
> >
> > This question came up more than 50 years ago in the age of Flathead
>(wrought
> > iron engine) powered dirt-track racing in stock cars and sprinters with
> > heating problems. One cure was a washer restrictor to slow down (?) the
> > flow. Everybody thought that was the reason, and it worked. Later we found
> > that the stock water pumps were cavitating (creating bubbles) from being
> > wound so tight and the washer increased the pressure on the pump and
>reduced
> > the tendency to cavitate. The bubbles reduced the contact of water to
> > wrought iron and caused real hot spots. Other cures included modifications
> > to the pump to reduce cavitation.
> >
> > Today's water pumps surely must be turning RPM's beyond their design RPM
> > and restrictors may be doing the same thing as they were doing 50 years
> > ago- reducing cavitation.
> > Dave the Hayseed
> > It's Spring in Nebraska
|