drilled thermostat

[supercharged93]

what are the advantages in having a drilled stat and can someone give me a link on the proper way to drill the thermostat and does it effect it in the winter time....thanks

[myfirstbonnie]

The drilled thermostat allows any air trapped in the system to be flushed to the radiator and expelled through the overflow. Thus you end up with a completely filled system. If air is trapped under the thermostat, it will take longer for the thermostat to reach opening temperature and risk overheating.

[supercharged93]

how do u drill it? what size hole do i drill and where on the stat do i drill?

[irkwerks2]

Techinfo is your friend...

http://www.pontiacbonnevilleclub.com/fo ... f=53&t=159

[2000Silverbullet]

The purpose of the factory ball check hole in the thermostat is just as Matt has stated, for bleeding air.

When the engine is used for drag racing where you try to cool the engine as much as possible and when temperatures rise very quickly against a closed therostat, the coolant gets very hot near the cylinder walls in the block and around combustion chambers.
A higher flow bypass is created by "drilling" larger holes, typically 1/16" - 3/16" diameter.
This maintains a small flow when the stat is closed, so hot spots are not created which could boil the coolant in that localized area. It also takes the engine longer to reach the stats rated temperature.

You can actually fine tune the stat by +/- 5 deg F using size and number of holes but need to be careful if your PCM still has the code enabled which monitors the amount of time it takes the engine to reach operating temperature.

[supercharged93]

thanks thats the link i was looking for..u guys are the best...