Paul,

 Thanks for the coolant flow rationale.
 Currently the Mazda pump pulls coolant from the rad and pushes it into
 the
 driver's side water passage per the info that you stated.  The coolant
 comes
 out of the block on the passengers' side and goes to the radiator.

 Would it be possible to place a stand alone  pump inlet at the outlet of
 the
 block on the passengers's side and push the water through the radiator
 then
 back into the block inlet on the driver's side?  The flow would be the
 same.
 The down side would be that the pump would see the hotest coolant.  Are
 there other issues?  Thanks for any help.

 Joe Berki
 Limo EZ

 You might get just steam from time to time.

 If you are mounting the remote pump down low that
 is the best place. If the water level is down the water input
 to the pump will still work.

 Paul Lamar



 Paul

 I believe you mean 'low' as in lower than the water reservoir tank
 level.
 Right?  That makes sense.

 Joe,  The issues of increasing the flow rate are  mostly related to
 plumbing
 restrictions and water density.  Pumping the off gassed  cooler water that
 is
 taken from  the bottom of the  vertical reservoir tank after exiting  the
 heat exchanger will be the coolest and hence most dense water.  Pumping
 higher density fluid will result in the best flow rate. Decreasing flow
 restrictions in the externals will increase flow.


 Pumping into the engine block first (like Mazda designed it) will
 subject
 the heat exchanger to less internal pressure then the vice versa route.
 Gentle angled  curves entering the inlet and outlet of all devices  will
 raise flow rate.One sharp elbow can cut the water flow almost 5%.
 Other
 than cutting the cooling grooves in the rotor housings ala Racing Beat,
 we
 can't do much  to improve flow characteristics of the engine, though I
 wish
 the cool water inlet was less turbulent.A 'once through' heat exchanger
 will flow much better than a dual pass heat exchanger and subject the heat
 exchanger to less pressure.

 Here is a good blurb about water heat exchangers.

 http://www.stewartcomponents.com/tech_tips/Tech_Tips_5.htm


 Doug in Japan.


 Doug,

 Thanks for the info.  I believe I can mount the remote pump low on the left
 side and move the alternator to the right side.  The problem with the Toyota
 pump and most of the scenarios that I can come up with involve elbows and
 restrictions such as the pump out let being smaller diameter creating more
 restriction.  The ironical thing about the block that I found to permit
 remote mounting is that it was used for a Stewart EWP in a car.

 Joe Berki
 Limo EZ

 http://www.stewartcomponents.net/Merchant2/
 merchant.mvc?Screen=PROD&Product_Code=E389A&Category_Code=ElectPump

 Stewart is a high integrity company so they make no ridicules claims
 about the suitability of their electric water pumps. To do so would
 ruin their reputation among major car manufactures in the world.
 Their electric pumps are designed to supplement the mechanical
 pumps rather than replace them. Do not use them stand alone.

 It takes about 3 HP to pump enough flow through the Mazda engine
 to cool the metal in the rotor housing at sustained full power.

 Electric pumps are far lower in HP.
 It works in drag racing as the engine only runs at full power
 for just a few seconds. Some drag engine do not even use cooling
 systems for that reason.

 Each HP requires 60 amps out of the alternator.
 To my knowledge no electric pumps come even close. There are no
 breakthrough impeller designs that would change this situation.
 In fact on the contrary some electric pumps have a less
 than optimum impeller design.

 My late rocket scientist friend Vance Jaqua built a 5 HP
 electric motor dyno to test water pumps.

 The physics has not changed.

 Paul Lamar

 --

Joe,


I too am trying to figure out how to mount the water pump down below the engine.  You mentioned on the left side.  Doesn't that place it near the hot muffler?

 I am using an earlier end housing like what is found on the 12A so perhaps I'll incorporate it  into the rear motor mount plate.  Yep! you are right about the challenges.   You almost have to machine, weld, and shape some special aluminum fittings to get the optimum pathway.

Pictured are the Stewart Component stainless racing pump, and a BMW timing plate cover  I had to cut the pump housing from.  I welded on a  different neck outlet that is much less restrictive in flow and expands tangentially out from the pump according to Steward engineers advice. As you can see in the last picture the BMW application has the water enter at quite an abrupt angle and perpendicular to the pumps water flow.   I'm  looking forward to testing the GPM  when my radiator arrives.

Doug in Japan

The BMW cartridge is hard to accommodate. Here is my 3D suggestion.
There are easier cartridges to work with.


Paul Lamar