Thermal issues, aka over heating question

[GregWeld]

Originally Posted by T/Aaron

I've been struggling with this one myself and so I drilled a small hole in the thermostat(I actually drilled a hole in each section as the LS1 has 2 flat areas that change with the temp). Seems to work fine now but will know for certain after a track day of course! Thanks for posting a real problem and seeing it through.

That was an old school trick to solve for pump cavation.... in other words - it was a bypass to allow some water to flow but also for air to be able to escape. Back in the day the cooling systems weren't "closed" like they are today.

Not saying this isn't something you can do... just saying there was a reason behind it "back in the day". The LS motors have the "steam vents" that are recirculated into the flow.. and the system should be closed to atmosphere via the use of the overflow can. That can should have enough coolant in it to cover the input - and be able to expand and contract without exposing the input tube. When cold - the input tube should be covered with coolant so that it doesn't draw air in as the motor cools down.


The other thing I've seen -- is the use of a radiator design where the return (to the radiator) hose inlet is near the radiator cap. There's a lot of pressure on that cap when the system is in full flow mode!