Head gasket coolant hole size?

[wedge5]

I was wondering why the coolant slit in the head gasket isn't bigger? The slit I am talking about is the one under the hole with the Ram head in it. You can see that it barely lets coolant through. You would think if they were bigger then the car would stay cooler.

 

[lewtot184]

i don't know the engineering whys or wherefors, but moving coolant thru the heads too fast will cause them to run hotter. its probably a design "control" to let the coolant travel at a rate that will let it transfer the most heat.

 

[Meep-Meep]

....Yep, or divert it to areas where it needs to be or balancing flow by adjusting the size of passages.

 

[wedge5]

See that makes sense to me. I was wondering if it had to do with flow rate control. Thanks guys

 

[68rt]

Head gasket coolant hole size

The slits are designed to hold water in the head/block longer (to restrict the flow) so the head and engine water will heat up. If the head gasket holes were the size of the water jacket, the cold water from the radiator dose not set in the block long enough to heat up so your send already cooler water back into the radiator. Don't ask me why, but I had a 70 rr /383 and over the course of a couple years the motor kept running cooler and cooler. I put in a new water pump, several thermostats and even carboard in front of the radiator in winter, and the temp. needle would bearly get off the peg to no availe. In winter the engine would not even warm up enought to realease the choak. I then took the heads off and the gasket in the water jacket had rotted away, allowing full flow through the block. Installed new head gaskets, problem solved.....

 

[67 coronet]

same idea as your thermostat.that is why they make restricters for thermostat removal on race applications.