whats the purpose of drilling the hole in the thermostat

[TurboII]

why do people drill the 1/16 hole in the the stat whats it for and why do peopel do it i havent done it yet on my car and thinking i should.

Thanks

[tryingbe]

http://www.thedodgegarage.com/turbo_tricks.html


"the real trick is a 1/16 hole drilled in the top of the thermostat. It prevents or lessens the "thermal shock" the engine sees when the thermostat opens for the first time and "shocks" the head and block with ice cold coolant from the radiator. 1/16 is about the perfect size, 1/8 is to large and causes the engine to run cooler then 180 degrees believe it or not."

It also help so you don't have the bleed the coolant system.

[TurboII]

lmao i was looking for that web site but i thought it was mini-mopars

[turbovanman²]

It works great and helps with the jumpy temp guage. Also, bleeding is now not needed.

[TurboJerry]

I like a 3/32" hole. It does all the above, but if the thermostat sticks shut, it gives you more time to react to it.......

[TurboII]

especially on a very cold day the gauage be boucing around and couldnt figure out way.

[GLHNSLHT2]

1/16 is too big. 3/32??!?! Are you kidding me? Why even have a t-stat. A .040" is just right.

[turbovanman²]

especially on a very cold day the gauage be boucing around and couldnt figure out way.


Bouncing guage is also a sign the heater core could be plugged. If you have crappy heat, you know why now.

[TurboJerry]

1/16 is too big. 3/32??!?! Are you kidding me? Why even have a t-stat. A .040" is just right.

That's because of the climate you live in. In California, 3/32" is an asset when the thermostat sticks closed and you need a few seconds to pull over, so .040" is too small here. By the time I get form my drive way to the second stop sign, the car is at operating temp. On V-8's I go 1/8" because they seem to have more thermal shock and are harder to bleed the air out then inline engines. I tried .040" and smaller, and it just isn't the same for me........

[puppet]

I like the thermo shock idea ... heh, too bad the flow is the other way.

[GLHNSLHT2]

We get up to Cali temps here in the summer. The .040" hole works fine. And 90% of the Tstats fail open now anyway.