C M Smith wrote:

Paul,
The table looks good. For quick pump work I use one atmosphere as 15

psi and 30 feet of

water; 2 feet per psi. Plenty good enough for small sizes of pump.

The efficiency of the cast impeller in an automotive paddle pump is

abysmal but it is easy

to cast and there is plenty of HP availble.

C M,

  Is there something that could be done to improve the design of the pump
impeller and possibly the housing to significantly improve this "abysmal"
factory design? We are far less cost driven than the factory is and I think
many of us would be willing to invest in an improved design that yielded a
significant increase in flow and cooling potential. Its been pointed out by
several people here over the years that the stock pump flow appears to be
marginal and that the cooling situation could be helped by improving the
flow potential of the pump.

  A couple of years ago Jeff Spitzer proposed to do just that and
supposedly  was prototyping and testing an improved design which he was
then going to make available to us. Unfortunately, nothing ever came of it.
I havent seen anything posted on here by Jeff in years. Is he even still on
here Paul?

Mike Wills

Most of the cast impellers in the  Mazda pumps look very good
compared to the sheet metal impellers I have seen in other brands.
Here is a picture of one of the worst Mazda ones. The Cosmo is better.
I think one would be lucky to get a single digit improvements
in the efficiency. After all, centrifugal pumps have probably
been around for at least 200 years.

I think the most important thing is matching the radiator resistance
the the characteristics of the water pump. The block does not
seem to be that big of a retarding force.

Paul Lamar
 
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