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Water pump?

Siestarider

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#1
While fooling with aero mods and cooling I have found some puzzles regarding water pump that maybe someone can help with. Seems it belongs here instead of Tracking thread.

1. I cannot find any information on our water pump flow rate per 1000 rpm. Mishimoto picked 40 gpm in their radiator testing, I assume at high rpm, as typical maximum. That sound right?
2. HP consumed by centrifugal wp looks like 3-6 hp on other performance cars, sound right for Fist?
3. 300 hp converts to 12,772 btu/min. Most of the experts say about 1/3 of this must be handled by engine cooling, water pump and radiator. So we have (for most of us) around 4000 btu/min maximum to waste via radiator.
4. Some racing guys increase water pumping rate to increase cooling, but I cannot find any water pump upgrades for us. Are there any?
5. Anyone messed with "high flow" thermostat to increase pumping and cooling? Is there even a high flow thermostat made for us?

Thanks

PS: According to all the math, stock radiator can handle 4000 btu/min easily. Is a bigger water pump a potential solution to track overheating?
 


Sourskittle

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#2
You can always add an electric pump inline. A pump feeding a pump means both pumps have an easy life
 


OP
S

Siestarider

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Thread Starter #3
I looked at the Ford parts diagrams, thermostat is contained within the engine outlet to radiator. Does not look easily accessible, may even have to remove radiator to get to it. But still, amazing to me that the only "better" cooling hardware developed so far for tracking is a larger radiator core. Seems a lot of other options exist but remain unexplored.
 


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Campbell
#4
Racers usually have to look for under drive pulleys for their water pumps to reduce the speed and prevent cavitations while running at high rpm.

I'm not 100% sure about this but I think auto engines are below 50% efficiency and the part that doesn't turn in to horsepower turns in to heat, I think that 4000 btu/minute is optimistically low.

Race engines that have to increase their flow rate probably have an electric water pump, if it was designed for a production car, it was probably designed for 90-100mph steady state, not hard tracking for a 20 minute session.

I haven't looked at the water pump, please post any info you find.

Some times there is a Saudi Arabia version of a production car with better cooling, we can look for part numbers if we find anything like that.
 


RAAMaudio

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#5
If I ever have a flow rate issue or other cooling and the big radiator, oil cooler, more air flow that is properly ducted, etc not able to keep up I will look into an electric water pump and remove the impeller from the stock unit as it is the easiest way to go around it. I have used them on a couple of pure track car builds, BMW and LS powered.

Stewart Electric pump, more than one version available, very reliable, flow as needed, not by engine RPM.



I have used one of these on inline BMW track cars as many do with great results as well and half the cost of the electric unit above.

Stewart belt driven pump.



I have also used quite a few sets of under drive water pump and alternator pulleys as well as AC pulleys on street driven cars, most often buying a complete set including crank pulley, a lot of gain in some applications.
 


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Siestarider

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Thread Starter #6
Racers usually have to look for under drive pulleys for their water pumps to reduce the speed and prevent cavitations while running at high rpm.

I'm not 100% sure about this but I think auto engines are below 50% efficiency and the part that doesn't turn in to horsepower turns in to heat, I think that 4000 btu/minute is optimistically low.

Race engines that have to increase their flow rate probably have an electric water pump, if it was designed for a production car, it was probably designed for 90-100mph steady state, not hard tracking for a 20 minute session.

Come on Wimp, pumping water is an easy calc, energy required does not change by how you do it, you are making s**t up. That whole underdrive cavitation line of argument is BS too.

Underdrive pully saves hp by pumping less water.

Cavitation is not a modern car water pump problem, assuming you are not overheating.

Modern engines may be 30% efficient, 70% heat, but only about half that heat goes to cooling water, most of the rest out exhaust. Which is why turbos are more efficient than superchargers, using waste heat is good.

I haven't looked at the water pump, please post any info you find.

I have looked, have a bunch of questions I could not find answers too, so get to work on answers and let us all know when you have some.

Some times there is a Saudi Arabia version of a production car with better cooling, we can look for part numbers if we find anything like that.

First useful idea in post, let us know what you find out.
 


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Campbell
#7
The underdrive cavitation is not BS. They do the same thing on alternators to save the bearings too.

Those are problems that racers see when using production style accessories on a race engine that is being operated at or above the stock RPM limit. NASCAR certainly does it and stock class drag racing to name two.

Most water pumps are cost reduced versions of pumps that were designed in the 60s, no fancy milled impellers or hydrodynamic inlets/outlets. Recently with manufacturers scrambling for efficiency, some of that is getting better but there is still a lot of crap out there.
 


RAAMaudio

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#8
Also some of us are spinning the engines much faster than the stock rev limit, at the moment highest I know of is 7,700 RPM which the stock pump might not be designed to work at.
 


haste

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#10
I wish are thermostats were easy to reach now that mishi has one out
Yeah, no doubt. I just changed the thermostat in my '02 SVT Focus for the first time and I could do it a 2nd time in about 15 minutes...
I haven't looked at the Fiesta ST location, yet.
 


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Campbell
#14
I have a Mishimoto radiator on the way so I should have more cooling capacity soon.

These days the thermostat setting are chosen for emissions requirements and engines make less emissions when running hot. I would seriously consider the Mishimoto thermostat if it was a high flow design or something but it seems to be a race style thermostat that just opens at a much lower temperature.

160° is just too low, if it was 180° I would order right away (according to Mishimoto stock is 207°).
 




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