[vex]

I think you're missing what I'm saying.

Originally Posted by NoDOHC

Fluid dynamics is applicable, but I think that heat transfer principles and metal expansion rates have more bearing in this situation.

Quite possibly and is something to consider. However the portion I was dealing with was the difference in the amount of fluid passing through the different passages. Not necessarily the heat transfer as this is two different issues of concern.

Technically, all passages have the same pressure across them (all tied to the same hose on one end, all rising the same amount, all exiting to atmosphere) The issue is that all passages have different flow rates due to their differing hydraulic diameter. The flow rate does not need to be consistent, as there is very little heat to be rejected at the beginning of the intake stroke as compared to the compression region.

Which I already stated.

We can solve for the hydraulic diameter given the (measured) flow much more easily than we can compute the other direction. Once again, this is not important, heat transfer is much more important here. Fast moving water is not always better.

Again, you're trying to tackle a different problem than to what I was referencing (not heat transfer).

Enlarging the passages is not always the best solution. What racing beat is doing is much better. They are increasing the surface area that is exposed to the cooling fluid while also inducing turbulence which improves convective heat transfer significantly.

Again, I wasn't discussing heat transfer specifically but balancing the mass flow between all passages. The heat transfer I did touch upon was coincidental and nothing more.

Once again, consistent passage-to-passage flow will not make this problem go away. The issue is much more complicated than that. The heat transferred to the coolant in each passage needs to be equal to the heat generated in the nearby chamber and transferred through the aluminum housing. I am guessing that Mazda did some research on this, as the coolant passages on top of the housing (low heat rejection to the coolant) have restrictors in them.

Again, I was only referencing the specific post I responded to.

I admire your attitude and your desire to apply your knowledge to any problem, I just don't want you wasting a lot of time chasing wild geese.

Asked and answered a question posted by Barry.