X-Mozilla-Keys:
David Carter wrote:
Bill Freeman wrote:
I really must be missing something here. So far all the
users flying behind and in front of Mazdas have ( I think) had at
least OK cooling, apparently with some intial airflow sorting processes,
but as I understand it, nothing heroic.
So why is it that there needs to be a 4X or 6X whatever increase
in the water flow?? Seems like just another way to get rid of
all those excess HPs laying around.
I'm confused because I expect that Jeff knows what is going
on, but I can't seem to figure out what the problem is that
is being solved. Been out in Colo at high altitude for nearly
a week, so maybe I'm still hypoxic. :-)
Help?
Bill
I personally am looking ahead Bill to at least 300 HP.
Most people have had to add extra radiators so we are
speculating that perhaps the water pump is not up to a
continuous 150 to 200 HP.
< snip >
David Carter comments to Bill,
Bill, you said, "Help" (understanding if there's anything to this thread on
water pump). For myself, I think the issue goes one level above "the
pump" - the issue we are talking about is "flow". The pump is only 1 part
of that "equation". Already, in the various responses, I've seen two items
that I feel are critical: 1) "Flow" output of the Mazda pump is affected
by any and all restrictions - it is not a positive displacement pump and any
restriction, like 2) (2nd critical point) coolant lines only being 1 inch
diameter (a -16 braided hose and fittings), or type of radiator, or
restrictions in engine block, etc), will reduce pumps flow. Even though
we've discussed the pump, that is not to be construed that we don't like the
pump or blame it for all cooling problems.
By the same token, we shouldn't assume or blame all the initial cooling
problems almost everyone has had on "air flow" problems through the
radiator. . . or thick vs thin . . . or angled vs straight fins. .etc.
Perhaps increasing airflow was one way, an adequate way, of improving
cooling. Who is to say that increasing coolant flow, if in fact it could be
increased significantly, wouldn't have been an equally effective solution to
a specific cooling deficiency?
Question for the experts: If we put on a "high output" racing pump, would
it be affected the same way by all the "restrictions" that the Mazda pump
is? Would it give any more flow, all other parts of the flow path being
equal? I don't know beans about pumps and the differences between them. I
don know about positive displacement hydraulic pumps (3000psi on fighters).
I think that as we focus on "flow" we should first focus on getting hoses
that are the same ID as the water pump inlet and outlets, and assuring that
our radiators and all fittings have that same ID, so none of them contribute
unnecessarily to "restrictions" to flow. Then, and maybe only then, should
we go for a higher output pump - if such a thing exists, i.e., if it could
put out a greater flow than the Mazda pump, given the same restrictions in
the flow path.
Thermostats, if used, must be racing thermostats. i.e., high flow - like
those sold by Stewart Components, the specialty cooling company with the
website we've recently re-visited.
I believe Paul has suggested adding the area of all the tubes in the
radiator to get their sum, which should be at least as big as the radiator
inlet and outlet. I had to do that on a Mercedes camshaft oiling system -
and found out that there was a serious restriction to oil flow at one point,
which I drilled out and "fixed" (during replacment of a severely damaged cam
shaft on a V-8). I do it all the time on every car I buy to assure that the
last/exit hole in the muffler has an area as big as the basic exhaust pipe
and the sum of exhaust ports (reduces flow, get more power, every time).
Did it to increase air filter inlet area on my two Ford Escort 1.9 engines -
major increase in power on the '93 (10 mpg gain in max speed the cruise
control would hold).
Finally, as I don't know if a "coolant flow meter" system exists, I suppose
the only way to quantify "total system flow" is to take off the hose from
radiator outlet and put it in a "calibrated bucket" (big bucket) to catch
coolant in given time, and have the water pump suck fresh coolant from
another (big) bucket/container, instead of from radiator outlet. Would be
analogous to how some folks check fuel flow through their system -
disconnect and measure how much you get in a given time.
David Carter
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