Coolant path hole in block

[Bolt]

There has been many posts about heat problems with these engines. While I have my heads off I found this coolent passage hole. It is only 1/8. Should it be larger to allow the coolent to flow or is this just a hole to allow the air to get out of the block when filling the coolent? What would happein if I drill it out to 1/4 inch? I always had high RPM heat build up. Could this be the problem or is this a factory error of not drilling it out larger? Anyone have any viler blocks laying around which you can take a picture of this area?

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[Garron]

I am looking at a gen 3 block and the port on the rear of the block is not even drilled at all.

 

[plumcrazy]

what kind of cats and exhaust ya sporting on it bolt ?

that could be the reason for heat buildup

 

[dave6666]

Isn't that where the sensor goes? And if so, would you want a lot of flow there? Once again maybe if so, the hole is small for a dampening effect on the sensor.

 

[Bolt]

what kind of cats and exhaust ya sporting on it bolt ?

that could be the reason for heat buildup

High flow.

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