I was lookin at one of my old rotor housings last night and noticed that around most of the water jacket, the holes are relatively small, sompared to the jacket it self. Has anyone ever tried enlarging these holes for better cooling? I would assume it's somewhat like a had gasket on a piston engine,allowing the exhaust side more flow due to it's higher temps, but shouldnt enlarging them all cool the engine better?

 

or too much. remember, not only is too hot bad but too cool is bad too. unless you are experiencing temp problems your are wasting your time. not to mention tht there are far easier methods such as a larger radiator, water wetter, etc.

 

Just throwin an idea around.......I think it would at least be a good idea to smooth out the flow transitions in the housings to try and eliminate some turbulance(sp) while I'm in there cleaning the passages out.

 

If I understand you correctly what you are talking about doing would actually reduce the cooling in the engine. Cooling is not all about flow. It is more about surface area. The more the coolant is touching metal the more of a chance it has to asorb the heat.

Many of the top engine builders offer a "water jacket modification" where they cut groves in the water jackets around the spark plug holes (apparently the hottest part of the engine) to give more surface area for the water to contact the housings.

 

as far as cooling goes turbulence is your friend.

 

Thepartstrader......good point about the flow thing......thanks.
So what do you think would happen if I added a hole here and there....not talking about making it look like a pasta strainer, but creating more surface area on the hotter "sides" of the engine(around plug holes and some just after)?

annuerysm---please explain to m why turbulance is your friend? I know that the right flow and surface area are important, but for the sake of discussion, what if you drain your block and dont completly bleed all the air out of your cooling system?Where there is turbulance, there's bound to be air, and a boiling spot in a housing. I imagine if Dr. Wankle, the fine folks at NSU and Mazda would have designed someway to create more turbulance than a relatively smooth water jacket if it was really necessary.
I'm not trying to be an *** but I've been studying engines for the majority of my life and I'm pretty sure trbulance, in large amounts, in a water cooled engine is generall not a good thing. But, like always, I could be wrong.